To restrict a users logon hours , use the net user command. These commands are used from the Command Prompt. (Start - RUN - and type cmd)
Below are some examples:
1 - net user Joanna /time:M-F,08:00-17:00
2 - net user Ninja /time:M-F,8am-5pm
3 - net user Echelon /time:M,4am-5pm;T,1pm-3pm;W-F,8:00-17:00
4 - net user Shine /time:all (this one means this user can always log on)
Note:You can only restrict when a user can log on to the system. On a stand alone computer, there is no way to force a user to log off when their hours expire, without a third party script or software.
How to restrict login hours allowed
|
How Long Has Your System Been Running?
|How Long Has Your System Been Running?
Here's how you verify system uptime:
Click Start | Run and type cmd to open a command prompt.
At the prompt, type systeminfo
Scroll down the list of information to the line that says System Up Time.
This will tell you in days, hours, minutes and seconds how long the system has been up.
Note that this command only works in XP Pro, not in XP Home. You can, however, type net statistics workstation at the prompt in Home. The first line will tell you the day and time that the system came online.
Guide to avoiding virus infections
|User's guide to avoiding virus infections
Keeping an eye out for viruses
Computer viruses are everywhere! This guide will show you how to stay alert and how to avoid getting infections on your computer. Having an updated virus scanner is only a small part of this, there are many ways that you can prevent having viruses other than a virus scanner, as it will not always save you.
Types of viruses
There are many type of viruses. Typical viruses are simply programs or scripts that will do various damage to your computer, such as corrupting files, copying itself into files, slowly deleting all your hard drive etc. This depends on the virus. Most viruses also mail themselves to other people in the address book. This way they spread really fast and appear at others' inboxes as too many people still fall for these. Most viruses will try to convince you to open the attachment, but I have never got one that tricked me. In fact, I found myself emailing people just to make sure they really did send me something. It does not hurt to be safe.
Worms
Worms are different type of viruses, but the same idea, but they are usually designed to copy themselves a lot over a network and usually try to eat up as much bandwidth as possible by sending commands to servers to try to get in. The code red worm is a good example of this. This worm breaks in a security hole in Microsoft IIS (Internet Information Server) in which is a badly coded http server that, despite the security risks, a lot of people use it. When the worm successfully gets in, it will try to go into other servers from there. When IceTeks was run on a dedicated server at my house, there was about 10 or so attempts per day, but because we ran Apache, the attempts did not do anything but waste bandwidth and not much as I had it fixed a special way. Some worms such as the SQL slammer will simply send themselves over and over so many times that they will clog up networks, and sometimes all of the internet. Worms usually affect servers more than home users, but again, this depends on what worm it is. It is suspected that most worms are efforts from the RIAA to try to stop piracy, so they try to clog up networks that could contain files. Unfortunately, the RIAA have the authority to do these damages and even if caught, nothing can be done.
Trojans
Trojans are another type of virus. They are simply like a server in which enables hackers to get into and control the computer. A trojan such as Subseven can enable a hacker to do various things such as control the mouse, eject the cd-rom drive, delete/download/upload files and much more.
MBR virues
Boot sector viruses are another type, they are similar to file viruses, but instead they go in the boot sector and can cause serious damage when the computer is booted, some can easily format your drive simply by booting your computer. These are hard to remove.
Most viruses have various characteristics. For example, a worm can also be a trojan and also infect the boot sector. It all depends on how the virus is written and what it is designed to do. That's why there are not really strong structured categories, as they can easily mix one in the other.
Know the potentially dangerous files
Like any other files, viruses must be opened in order to do something. Most viruses come through e-mail as an attachment. Some will make it look like it's someone you know, and it will try to convince you to open an attachment. Never open attachments at any cost! Some viruses will infect files in programs, so opening a program will actually open the virus, maybe the same one, or another part of it.
All files have what is called an extension; This is the 3 last letters after the last period. For example, setup.exe has a file extension of .exe.
Extensions to watch out for are .exe .com .bat .scr .pif .vbs and others, but these are the most seen. .exe .com .bat .pif and .scr are valid extensions for executables. A virus writer will simply rename it to one of these and it will work the same way. .pif is a shortcut to an ms-dos program and will have the ms dos icon, but will still execute whatever code is in it, so an .exe can be renamed to .pif and be run the same way. .bat is a batch file, which can contain instructions to do various file activities, but again, a .exe can be renamed to .bat and it will execute it! .vbs is a visual basic script. For some reason, Microsoft provides this scripting language along with the scripting host to make it more convenient to design and write viruses quickly and easily, I've never seen another use for this scripting language other than for writing viruses. There are programs that are written with that language, but it is compiled into an exe. Exe is the usual extension for programs, you would not have a software CD install a bunch of vbs files all over!
Bottom line is, if you don't know what a file is just don't open it. Some viruses will sometimes be named a way as to mask the real file extension to make it look like a harmless file such as a image file. This is easily noticed, but can still be missed. Simply don't open unexpected files.
If you get something that appears like something legit, just ask the person it came from if they sent it. Most viruses use a friend's address to make it look like it comes from them. The virus does this by using the person's address when sending itself to the address book contacts.
Downloads
Email is not the only way to get viruses; P2P (file sharing programs such as kazaa, winmx, direct connect etc) is also another way to get viruses.
When downloading programs, the main thing to watch out for is the file size. If you are downloading a program that you expect to be rather large such as a game, don't grab a file that is 10KB, since it's most likely a virus. However, I've been caught with a virus even with large files, so file size is not the only thing to watch, as an exe is still valid even if junk is added at the end, so a 64KB virus will still function even if it is turned into 650MB.
Icons are something to look for too, fortunately, virus writers don't take time to put icons. If your download should be a setup file, you should see the icon of a setup file. If it's just the blank icon that typical plain or corrupted exes have, don't open it.
Another thing to do, which should be obvious, is to scan the file for viruses using updated virus definitions. But don't rely on only your virus scanner, as they are not perfect, and if the virus has not been reported to them yet, they won't know to create a definition for it!
Changing settings to stay safe
If you do open a virus, you want to avoid it going to all your friends. The simplest thing to do is to NOT use the windows address book. It is easy for viruses to get through and Microsoft is not doing anything about it. Just don't use it. Put them in spreadsheet or even better write them down somewhere. Don't use the address book.
Another "feature" to avoid is the auto preview. Some viruses can attempt to open themselves just by opening the email. There are security holes in Microsoft mail programs that allow this. In Microsoft Outlook, click on the view menu and remove auto preview. You need to do this for every folder, but the inbox is most important. In Outlook Express, click on the view menu and go to layout. In the dialog box, you will see a check box for show preview pane. Uncheck it and click ok.
Another thing you should change, especially if you download a lot, is the option that allows you to view the file extension. In Win98, go in any folder, click on view then folder options and choose the view tab and where it says hide file extension for known types, uncheck it. In win2k, it is the same process, but instead, go in the control panel and open the folder options icon.
Avoiding server worms
Some viruses, mostly worms, can exploit through servers and affect other servers from servers that have been infected. A good example is the SQL slammer. This was a worm that affected SQL servers run by Microsoft IIS and Microsoft SQL Server. Once the worm gets in, that particular server starts trying to find more exploitable driving internet connections to a halt in the process. Servers running Apache were unaffected by that, except for the many hits to try to get in. IceTeks received about 100 hits per day when it was run on a dedicated home server. Most hits came from major ISPs and other big websites that had no clue they were still affected.
The simple solution to avoid these types of viruses is to NOT use Microsoft based server software for your server, especially if it is a public server. The operating system is also crucial, but the actual server software is much more. Apache, which is free, is much more secure than Microsoft based server programs such as IIS. IIS may be easier to understand and administer, but it saves a lot of hassle to learn how to use Apache. IIS has a large number of vulnerabilities, such as the ability to gain access to cmd.exe and basically delete the whole drive by doing a ../ request in the address bar. These don't require viruses, but simply commands, but there are worms written to automatically make these commands. The code red does this.
Removing a virus
The best way to do this is to do a clean install. However, depending on how bad the virus is, a simple clean install won't remove it. So to be extra sure, you'll want to do a low level format. This is especially true of you got a boot sector virus, as even repartitioning and formatting won't quite remove it, but sometimes you can get away with an fdisk /mbr, but not all the time. here are various removal tools for viruses, it is good to use them and see if they work, but proceeding with the clean install is recommended. You never know if the virus is completely removed by deleting files you suspect are infected. Some viruses such as the Bugbear will close anti virus programs and other programs to make it hard and annoying to figure out what to do. A clean install is the best way to ensure that it's gone for good.
Viruses are out there, don't be one of the many infected ones! Stay alert and stay safe! Don't open unexpected files, regularly update your virus definitions and scan downloaded files!
I hope this article was useful for you!
Make Autorun for your CD
|If you wanna make a autorun file for that CD you are ready to burn just read this...
1) You open notepad
2) now you write: [autorun]
OPEN=INSTALL\Setup_filename.EXE
ICON=INSTALL\Setup_filename.EXE
Now save it but not as a .txt file but as a .inf file.
But remember! The "Setup_filename.EXE" MUST be replaced with the name of the setup file. And you also need to rember that it is not all of the setup files there are called '.exe but some are called '.msi
3) Now burn your CD with the autorun .inf file included.
4) Now set the CD in you CD drive and wait for the autorun to begin or if nothing happens just double-click on the CD drive in "This Computer"
How to Bypass BIOS Passwords - Tutorial
|How to Bypass BIOS Passwords
BIOS passwords can add an extra layer of security for desktop and laptop computers. They are used to either prevent a user from changing the BIOS settings or to prevent the PC from booting without a password. Unfortunately, BIOS passwords can also be a liability if a user forgets their password, or changes the password to intentionally lock out the corporate IT department. Sending the unit back to the manufacturer to have the BIOS reset can be expensive and is usually not covered in the warranty. Never fear, all is not lost. There are a few known backdoors and other tricks of the trade that can be used to bypass or reset the BIOS
DISCLAIMER
This article is intended for IT Professionals and systems administrators with experience servicing computer hardware. It is not intended for home users, hackers, or computer thieves attempting to crack the password on a stolen PC. Please do not attempt any of these procedures if you are unfamiliar with computer hardware, and please use this information responsibly. LabMice.net is not responsible for the use or misuse of this material, including loss of data, damage to hardware, or personal injury.
Before attempting to bypass the BIOS password on a computer, please take a minute to contact the hardware manufacturer support staff directly and ask for their recommended methods of bypassing the BIOS security. In the event the manufacturer cannot (or will not) help you, there are a number of methods that can be used to bypass or reset the BIOS password yourself. They include:
Using a manufacturers backdoor password to access the BIOS
Use password cracking software
Reset the CMOS using the jumpers or solder beads.
Removing the CMOS battery for at least 10 minutes
Overloading the keyboard buffer
Using a professional service
Please remember that most BIOS passwords do not protect the hard drive, so if you need to recover the data, simply remove the hard drive and install it in an identical system, or configure it as a slave drive in an existing system. The exception to this are laptops, especially IBM Thinkpads, which silently lock the hard drive if the supervisor password is enabled. If the supervisor password is reset without resetting the and hard drive as well, you will be unable to access the data on the drive.
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Backdoor passwords
Many BIOS manufacturers have provided backdoor passwords that can be used to access the BIOS setup in the event you have lost your password. These passwords are case sensitive, so you may wish to try a variety of combinations. Keep in mind that the key associated to "_" in the US keyboard corresponds to "?" in some European keyboards. Laptops typically have better BIOS security than desktop systems, and we are not aware of any backdoor passwords that will work with name brand laptops.
WARNING: Some BIOS configurations will lock you out of the system completely if you type in an incorrect password more than 3 times. Read your manufacturers documentation for the BIOS setting before you begin typing in passwords
Award BIOS backdoor passwords:
ALFAROME ALLy aLLy aLLY ALLY aPAf _award AWARD_SW AWARD?SW AWARD SW AWARD PW AWKWARD awkward BIOSTAR CONCAT CONDO Condo d8on djonet HLT J64 J256 J262 j332 j322 KDD Lkwpeter LKWPETER PINT pint SER SKY_FOX SYXZ syxz shift + syxz TTPTHA ZAAADA ZBAAACA ZJAAADC 01322222
589589 589721 595595 598598
AMI BIOS backdoor passwords:
AMI AAAMMMIII BIOS PASSWORD HEWITT RAND AMI?SW AMI_SW LKWPETER A.M.I. CONDO
PHOENIX BIOS backdoor passwords:
phoenix, PHOENIX, CMOS, BIOS
MISC. COMMON PASSWORDS
ALFAROME BIOSTAR biostar biosstar CMOS cmos LKWPETER lkwpeter setup SETUP Syxz Wodj
OTHER BIOS PASSWORDS BY MANUFACTURER
Manufacturer Password
VOBIS & IBM merlin
Dell Dell
Biostar Biostar
Compaq Compaq
Enox xo11nE
Epox central
Freetech Posterie
IWill iwill
Jetway spooml
Packard Bell bell9
QDI QDI
Siemens SKY_FOX
TMC BIGO
Toshiba Toshiba
TOSHIBA BIOS
Most Toshiba laptops and some desktop systems will bypass the BIOS password if the left shift key is held down during boot
IBM APTIVA BIOS
Press both mouse buttons repeatedly during the boot
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Password cracking software
The following software can be used to either crack or reset the BIOS on many chipsets. If your PC is locked with a BIOS administrator password that will not allow access to the floppy drive, these utilities may not work. Also, since these utilities do not come from the manufacturer, use them cautiously and at your own risk.
Cmos password recovery tools 3.1
!BIOS (get the how-to article)
RemPass
KILLCMOS
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Using the Motherboard "Clear CMOS" Jumper or Dipswitch settings
Many motherboards feature a set of jumpers or dipswitches that will clear the CMOS and wipe all of the custom settings including BIOS passwords. The locations of these jumpers / dipswitches will vary depending on the motherboard manufacturer and ideally you should always refer to the motherboard or computer manufacturers documentation. If the documentation is unavailable, the jumpers/dipswitches can sometimes be found along the edge of the motherboard, next to the CMOS battery, or near the processor. Some manufacturers may label the jumper / dipswitch CLEAR - CLEAR CMOS - CLR - CLRPWD - PASSWD - PASSWORD - PWD. On laptop computers, the dipswitches are usually found under the keyboard or within a compartment at the bottom of the laptop.
Please remember to unplug your PC and use a grounding strip before reaching into your PC and touching the motherboard. Once you locate and rest the jumper switches, turn the computer on and check if the password has been cleared. If it has, turn the computer off and return the jumpers or dipswitches to its original position.
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Removing the CMOS Battery
The CMOS settings on most systems are buffered by a small battery that is attached to the motherboard. (It looks like a small watch battery). If you unplug the PC and remove the battery for 10-15 minutes, the CMOS may reset itself and the password should be blank. (Along with any other machine specific settings, so be sure you are familiar with manually reconfiguring the BIOS settings before you do this.) Some manufacturers backup the power to the CMOS chipset by using a capacitor, so if your first attempt fails, leave the battery out (with the system unplugged) for at least 24 hours. Some batteries are actually soldered onto the motherboard making this task more difficult. Unsoldering the battery incorrectly may damage your motherboard and other components, so please don't attempt this if you are inexperienced. Another option may be to remove the CMOS chip from the motherboard for a period of time.
Note: Removing the battery to reset the CMOS will not work for all PC's, and almost all of the newer laptops store their BIOS passwords in a manner which does not require continuous power, so removing the CMOS battery may not work at all. IBM Thinkpad laptops lock the hard drive as well as the BIOS when the supervisor password is set. If you reset the BIOS password, but cannot reset the hard drive password, you may not be able to access the drive and it will remain locked, even if you place it in a new laptop. IBM Thinkpads have special jumper switches on the motherboard, and these should be used to reset the system.
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Overloading the KeyBoard Buffer
On some older computer systems, you can force the CMOS to enter its setup screen on boot by overloading the keyboard buffer. This can be done by booting with the keyboard or mouse unattached to the systems, or on some systems by hitting the ESC key over 100 times in rapid succession.
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Jumping the Solder Beads on the CMOS
It is also possible to reset the CMOS by connecting or "jumping" specific solder beads on the chipset. There are too many chipsets to do a breakdown of which points to jump on individual chipsets, and the location of these solder beads can vary by manufacturer, so please check your computer and motherboard documentation for details. This technique is not recommended for the inexperienced and should be only be used as a "last ditch" effort.
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Using a professional service
If the manufacturer of the laptop or desktop PC can't or won't reset the BIOS password, you still have the option of using a professional service. Password Crackers, Inc., offers a variety of services for desktop and laptop computers for between $100 and $400. For most of these services, you'll need to provide some type of legitimate proof of ownership. This may be difficult if you've acquired the computer second hand or from an online auction.
Backtracking Email Messages ( find out real spamer!)
|Backtracking EMAIL Messages
Tracking email back to its source: Twisted Evil
cause i hate spammers... Evil or Very Mad
Ask most people how they determine who sent them an email message and the response is almost universally, "By the From line." Unfortunately this symptomatic of the current confusion among internet users as to where particular messages come from and who is spreading spam and viruses. The "From" header is little more than a courtesy to the person receiving the message. People spreading spam and viruses are rarely courteous. In short, if there is any question about where a particular email message came from the safe bet is to assume the "From" header is forged.
So how do you determine where a message actually came from? You have to understand how email messages are put together in order to backtrack an email message. SMTP is a text based protocol for transferring messages across the internet. A series of headers are placed in front of the data portion of the message. By examining the headers you can usually backtrack a message to the source network, sometimes the source host. A more detailed essay on reading email headers can be found .
If you are using Outlook or Outlook Express you can view the headers by right clicking on the message and selecting properties or options.
Below are listed the headers of an actual spam message I received. I've changed my email address and the name of my server for obvious reasons. I've also double spaced the headers to make them more readable.
Return-Path:
X-Original-To: davar@example.com
Delivered-To: davar@example.com
Received: from 12-218-172-108.client.mchsi.com (12-218-172-108.client.mchsi.com [12.218.172.108])
by mailhost.example.com (Postfix) with SMTP id 1F9B8511C7
for
Received: from (HELO 0udjou) [193.12.169.0] by 12-218-172-108.client.mchsi.com with ESMTP id <536806-74276>; Sun, 16 Nov 2003 19:42:31 +0200
Message-ID:
From: "Maricela Paulson"
Reply-To: "Maricela Paulson"
To: davar@example.com
Subject: STOP-PAYING For Your PAY-PER-VIEW, Movie Channels, Mature Channels...isha
Date: Sun, 16 Nov 2003 19:42:31 +0200
X-Mailer: Internet Mail Service (5.5.2650.21)
X-Priority: 3
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="MIMEStream=_0+211404_90873633350646_4032088448"
According to the From header this message is from Maricela Paulson at s359dyxxt@yahoo.com. I could just fire off a message to abuse@yahoo.com, but that would be waste of time. This message didn't come from yahoo's email service.
The header most likely to be useful in determining the actual source of an email message is the Received header. According to the top-most Received header this message was received from the host 12-218-172-108.client.mchsi.com with the ip address of 21.218.172.108 by my server mailhost.example.com. An important item to consider is at what point in the chain does the email system become untrusted? I consider anything beyond my own email server to be an unreliable source of information. Because this header was generated by my email server it is reasonable for me to accept it at face value.
The next Received header (which is chronologically the first) shows the remote email server accepting the message from the host 0udjou with the ip 193.12.169.0. Those of you who know anything about IP will realize that that is not a valid host IP address. In addition, any hostname that ends in client.mchsi.com is unlikely to be an authorized email server. This has every sign of being a cracked client system.
Here's is where we start digging. By default Windows is somewhat lacking in network diagnostic tools; however, you can use the tools at to do your own checking.
davar@nqh9k:[/home/davar] $whois 12.218.172.108
AT&T WorldNet Services ATT (NET-12-0-0-0-1)
12.0.0.0 - 12.255.255.255
Mediacom Communications Corp MEDIACOMCC-12-218-168-0-FLANDREAU-MN (NET-12-218-168-0-1)
12.218.168.0 - 12.218.175.255
# ARIN WHOIS database, last updated 2003-12-31 19:15
# Enter ? for additional hints on searching ARIN's WHOIS database.
I can also verify the hostname of the remote server by using nslookup, although in this particular instance, my email server has already provided both the IP address and the hostname.
davar@nqh9k:[/home/davar] $nslookup 12.218.172.108
Server: localhost
Address: 127.0.0.1
Name: 12-218-172-108.client.mchsi.com
Address: 12.218.172.108
Ok, whois shows that Mediacom Communications owns that netblock and nslookup confirms the address to hostname mapping of the remote server,12-218-172-108.client.mchsi.com. If I preface a www in front of the domain name portion and plug that into my web browser, http://www.mchsi.com, I get Mediacom's web site.
There are few things more embarrassing to me than firing off an angry message to someone who is supposedly responsible for a problem, and being wrong. By double checking who owns the remote host's IP address using two different tools (whois and nslookup) I minimize the chance of making myself look like an idiot.
A quick glance at the web site and it appears they are an ISP. Now if I copy the entire message including the headers into a new email message and send it to abuse@mchsi.com with a short message explaining the situation, they may do something about it.
But what about Maricela Paulson? There really is no way to determine who sent a message, the best you can hope for is to find out what host sent it. Even in the case of a PGP signed messages there is no guarantee that one particular person actually pressed the send button. Obviously determining who the actual sender of an email message is much more involved than reading the From header. Hopefully this example may be of some use to other forum regulars.
Speed up your bandwidth by 20 % !
|Windows uses 20% of your bandwidth Here's how to Get it back
A nice little tweak for XP. Microsoft reserve 20% of your available bandwidth for their own purposes (suspect for updates and interrogating your machine etc..)
Here's how to get it back:
Click Start-->Run-->type "gpedit.msc" without the "
This opens the group policy editor. Then go to:
Local Computer Policy-->Computer Configuration-->Administrative Templates-->Network-->QOS Packet Scheduler-->Limit Reservable Bandwidth
Double click on Limit Reservable bandwidth. It will say it is not configured, but the truth is under the 'Explain' tab :
"By default, the Packet Scheduler limits the system to 20 percent of the bandwidth of a connection, but you can use this setting to override the default."
So the trick is to ENABLE reservable bandwidth, then set it to ZERO.
This will allow the system to reserve nothing, rather than the default 20%.
I have tested on XP Pro, and 2000
other o/s not tested.
Please give me feedback about your results
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