Computer viruses: description, prevention, and recovery

What is a laptop virus?
A bug may be a little software program that spreads from one laptop to a different laptop which interferes with laptop operation. A bug might corrupt or delete knowledge on a laptop, use an e-mail program to unfold the virus to alternative computers, or perhaps delete everything on the arduous disk.

Computer viruses are most simply unfold by attachments in e-mail messages or by instant messaging messages. Therefore, you want to never open an e-mail attachment unless you recognize who sent the message or unless you're expecting the e-mail attachment. laptop viruses may be disguised as attachments of funny pictures, greeting cards, or audio and video files. laptop viruses conjointly unfold by using downloads on the web. laptop viruses may be hidden in pirated software or in alternative files or programs that you simply might download.



Symptoms that will be the results of normal Windows functions
A bug infection might cause the subsequent problems:
Note: These issues may additionally occur as a result of normal Windows functions or issues in Windows that don't seem to be caused by a bug.

    * Windows doesn't begin even if you have got not created any system changes or perhaps though you have got not put in or removed any programs.
    * Windows doesn't begin as a result of bound vital system files are missing. Additionally, you receive a mistake message that lists the missing files.
    * the pc generally starts for sure. However, at alternative times, the pc stops responding before the desktop icons and also the taskbar seem.
    * the pc runs terribly slowly. Additionally, the pc takes longer than expected to start out.
    * You receive out-of-memory error messages even if the pc has sufficient RAM.
    * New programs are put in incorrectly.
    * Windows spontaneously restarts unexpectedly.
    * Programs that used to run stop responding frequently. though you take away and reinstall the programs, the problem continues to occur.
    * A disk utility like Scandisk reports multiple serious disk errors.
    * A partition disappears.
    * the pc forever stops responding after you attempt to use Microsoft workplace merchandise.
    * you can't begin Windows Task Manager.
    * Antivirus software indicates that a bug is gift.


Symptoms of a bug

If you believe or make sure that your laptop is infected with a bug, acquire the present antivirus software. the subsequent are some primary indicators that a laptop could also be infected:

    * the pc runs slower than usual.
    * the pc stops responding, or it locks up frequently.
    * the pc crashes, and then it restarts each jiffy.
    * the pc restarts on its own. Additionally, the pc doesn't run as usual.
    * Applications on the pc don't work properly.
    * Disks or disk drives are inaccessible.
    * you can't print things properly.
    * You see uncommon error messages.
    * You see distorted menus and dialog boxes.
    * there's a double extension on an attachment that you simply recently opened, such as a .jpg, .vbs, .gif, or .exe. extension.
    * An antivirus program is disabled for no reason. Additionally, the antivirus program can not be restarted.
    * An antivirus program can not be put in on the pc, or the antivirus program won't run.
    * New icons seem on the desktop that you simply failed to place there, or the icons don't seem to be related to any recently put in programs.
    * Strange sounds or music plays from the speakers unexpectedly.
    * A program disappears from the pc even if you probably did not intentionally take away the program.

Note These are common signs of infection. However, these signs may additionally be caused by hardware or software issues that don't have anything to try and do with a bug. Unless you run the Microsoft Malicious Software Removal Tool, and then you put in industry-standard, up-to-date antivirus software on your laptop, you can't make sure whether or not a laptop is infected with a bug or not.

Symptoms of worms and computer program viruses in e-mail messages
When a bug infects e-mail messages or infects alternative files on a laptop, you will notice the subsequent symptoms:

    * The infected file might build copies of itself. This behavior might fritter away all the free house on the arduous disk.
    * a duplicate of the infected file could also be sent to all or any the addresses in an e-mail address list.
    * the pc virus might reformat the arduous disk. This behavior can delete files and programs.
    * the pc virus might install hidden programs, like pirated software. This pirated software might then be distributed and sold from the pc.
    * the pc virus might cut back security. this might enable intruders to remotely access the pc or the network.
    * You receive an e-mail message that incorporates a strange attachment. after you open the attachment, dialog boxes seem, or a sudden degradation in system performance happens.
    * somebody tells you that they need recently received e-mail messages from you that contained connected files that you simply failed to send. The files that are connected to the e-mail messages have extensions like .exe, .bat, .scr, and .vbs extensions.

What is Spyware?
Spyware will install on your laptop while not your information. These programs will modification your computer’s configuration or collect advertising knowledge and private data. Spyware will track web looking out habits and presumably redirect net web site activity.

Symptoms of Spyware
When a laptop becomes littered with Spyware, the subsequent might result:

    * Slow web affiliation.
    * Changing your net browser’s home page.
    * Loss of web connectivity.
    * Failure to open some programs, together with security software.
    * Unable to go to specific websites, which can embody redirecting you to a different one.

How to take away a bug and spyware.
Even for an professional, removing a bug or spyware may be a tough task while not the assistance of laptop malicious software removal tools. Some laptop viruses and alternative unwanted softwarereinstall themselves when the viruses and spyware are detected and removed. Fortunately, by updating the pc and by using malicious software removal tools, you'll facilitate permanently take away unwanted software.

To remove a bug and alternative malicious software, follow these steps:

Install the most recent updates from Microsoft Update:

   1. For Windows Vista and Windows 7:
         1. Click the Pearl (Start) button, then sort Windows Update within the search box.
         2. within the results space, click Windows Update.
         3. Click Check for Updates.
         4. Follow the directions to download and install the most recent Windows Updates.
   2. For Windows XP:
         1. Click begin, then click Run.
         2. Type sysdm.cpl and press the Enter key.
         3. Click the automated Updates tab and select the automated (recommended) choice.
         4. Click OK.

Use the Microsoft Safety Scanner

Microsoft offers a free on-line tool which will scan and take away potential threats from your laptop. To perform the scan, visit: http://www.microsoft.com/security/scanner/ (http://www.microsoft.com/security/scanner/)

Install and run Microsoft Security necessities

Microsoft offers a free malicious removal program; Microsoft Security necessities which will conjointly facilitate shield your laptop from being infected. to put in Microsoft Security necessities, follow the steps below:

   1. visit the Microsoft Security necessities web site at: http://www.microsoft.com/security_essentials/ (http://www.microsoft.com/security_essentials/)
   2. Click Download currently.
   3. If your browser prompts you to save lots of or run the file, click Run.
   4. Follow the steps to put in Microsoft Security necessities.
   5. when installation, restart your laptop and open Microsoft Security necessities.
   6. On the house tab, select the complete scan choice, and then click Scan currently.

For a lot of data regarding a way to take away a bug, visit the subsequent Microsoft net site: http://www.microsoft.com/protect/computer/viruses/remove.mspx

How to shield your laptop against viruses
To protect your laptop against viruses, follow these steps:

   1. activate the firewall.
         1. For data on a way to activate your firewall with Windows XP, visit: http://support.microsoft.com/kb/283673 (http://support.microsoft.com/kb/283673)
         2. For data on a way to activate your firewall with Windows Vista, visit: http://windows.microsoft.com/en-US/windows-vista/Turn-Windows-Firewall-on-or-off (http://windows.microsoft.com/en-US/windows-vista/Turn-Windows-Firewall-on-or-off)
         3. For data on a way to activate your firewall with Windows seven, visit: http://windows.microsoft.com/en-US/windows7/Turn-Windows-Firewall-on-or-off (http://windows.microsoft.com/en-US/windows7/Turn-Windows-Firewall-on-or-off)
   2. Keep your laptop up-to-date.
         1. For data on a way to set Automatic Updates in Windows, visit: http://support.microsoft.com/kb/306525 (http://support.microsoft.com/kb/306525)
   3. Install Microsoft Security necessities and keep it up to this point.
         1. For a lot of data on a way to install and use Microsoft Security necessities, visit: http://www.microsoft.com/security_essentials/default.aspx (http://www.microsoft.com/security_essentials/default.aspx)

For a lot of data regarding a way to shield a laptop against viruses, visit the subsequent Microsoft net site:
http://www.microsoft.com/protect/computer/default.mspx

What are rogue virus alerts?

Rogue security software programs can attempt to cause you to suppose that your machine is infected by an endemic and typically prompt you to download and/or get a removal product. The names of those merchandise sometimes contain words like “Antivirus,” “Shield,” “Security,” Protection,” “Fixer,” so that they seem to be legitimate. they'll typically run immediately when downloaded, or succeeding time your laptop starts up. Rogue security software will forestall applications from gap, together with web Explorer, and will show legitimate and extremely vital Windows files as infections. Some typical error messages or pop ups {you might|you'll|you will} receive may contain:

Warning!
Your laptop is infected!
This laptop is infected by spyware and adware.

A good sign that the software isn't helpful to you is that after you attempt to shut the window it'll frequently pop up warnings similar to:

Are you positive you wish to navigate from this page?
Your laptop is infected! they'll cause knowledge lost and file corruption and wish to be treated as soon as potential. Press CANCEL to forestall it. come back to System Security and download it to secure your computer.
Press okay to Continue or Cancel to remain on the present page.

It is strongly suggested that you simply do not download or purchase any reasonably software that advertises during this manner.

How to take away rogue software

If you're feeling you have got rogue software on your laptop Microsoft has offered variety of how to assist you take away it.

Use the free Microsoft Safety Scanner

Microsoft offers a free on-line tool which will scan and take away potential threats from your laptop. To perform the scan, visit: http://www.microsoft.com/security/scanner/ (http://www.microsoft.com/security/scanner/)

Download and install Microsoft Security necessities

Microsoft Security necessities may be a free tool which will facilitate forestall rogue software, viruses, and alternative malicious programs from putting in on your laptop further as take away them. Once you have got finished using the Microsoft Safety Scanner, install Microsoft Security necessities. To do so, follow the steps below:

   1. visit the Microsoft Security necessities web site at: http://www.microsoft.com/security_essentials (http://www.microsoft.com/security_essentials)
   2. Click Download currently.
   3. Follow the steps within the Installation Wizard to put in Microsoft Security necessities.


Manually take away the rouge software

If the rogue software can not be detected or removed using Microsoft Safety Scanner and/or Microsoft Security necessities, strive the steps below to find the offending program and delete it:

   1. Write down the name of the rogue software. For this instance we'll decision it XP Security Agent 2010.
   2. begin Windows in Safe Mode with Networking:
         1. Restart your laptop.
         2. after you see the computer's manufacturer's brand, press and hold the F8 key.
         3. When prompted, use the arrow keys to focus on Safe Mode with Networking and press the Enter key.
   3. Click begin and check to check if the rogue software seems within the begin menu. during this case, we'll decision it XP Security Agent 2010. If it is not listed there, click All Programs and scroll to search out the rogue software's name.
   4. Right-click the offending program, then click Properties.
   5. Click the Shortcut tab.
   6. within the Properties dialogue box, check the trail of the rogue program listed in Target. For this instance, it'll seem as: C:\Program Files\ XP Security Agent 2010. Note: The folder name can typically seem as a random variety.
   7. Click Open File Location.
   8. within the Program Files window, click Program Files within the address bar.
   9. Scroll till you discover the offending program folder. For this instance, it'll be named XP Security Agent 2010.
  10. Right-click the folder, then click Delete.
  11. Restart your laptop.
  12. visit the Microsoft Safety Scanner web site at:  http://www.microsoft.com/security/scanner/ (http://www.microsoft.com/security/scanner/)
  13. Follow the steps to run the scan and take away the offending rogue software.

If you believe that your laptop is infected with rogue security software that's currently not detected with Microsoft security solutions, you'll submit samples using the Microsoft Malware Protection Center submission kind (https://www.microsoft.com/security/portal/Submission/Submit.aspx) .

For a lot of data on rogue security software, visit the subsequent Microsoft net sites:

http://www.microsoft.com/security/antivirus/rogue.aspx
http://www.microsoft.com/security/pc-security/antivirus-rogue.aspx

How to reset your web Explorer proxy settings
Malicious software might modification Windows web Explorer proxy settings, and these changes will forestall you from accessing Windows Update or any Microsoft Security sites.

To change your web Explorer proxy settings, follow the steps below:

   1. On a non-infected laptop go to: http://support.microsoft.com/kb/2289942 (http://support.microsoft.com/kb/2289942)
   2. Go the Fix it on behalf of me section.
   3. Click the Fix it button and when prompted, reserve it to a flash drive or a CD.
   4. Insert the flash drive or CD to the infected laptop.
   5. begin Windows, click begin, and then click Run.
   6. Click Browse.
   7. select the placement of the flash drive or CD. The file ought to be displayed. Double click the file and then click Open.

To change the settings yourself, follow the steps below:

   1. On Windows XP, click begin, or on Windows Vista or Windows seven, click the Pearl (Start) button, and then click Run.
   2. within the Run text box, copy (CTRL+C) and paste (CTRL+V) or sort the following: reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings" /v ProxyEnable /t REG_DWORD /d zero /f
   3. Click OK.
   4. On Windows XP, click begin, or on Windows Vista or Windows seven, click the Pearl (Start) button, and then click Run.
   5. In theRuntext box, copy (CTRL+C) and paste (CTRL+V) or sort the following: reg delete "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings" /v ProxyServer /f
   6.  Click OK.

How to acquire bug and security-related support
For u.  s. and Canada
The computer safety team is accessible for bug and for alternative security-related support twenty four hours daily within the u.  s. and in Canada.

To obtain bug and security-related support, follow these steps:

   1. Before you contact a support engineer, make certain that you simply run updated antivirus software and updated spyware removal software on the infected laptop.

      For a lot of data regarding a way to acquire a free laptop safety scan, visit the subsequent Microsoft net site: http://www.microsoft.com/security/scanner/ (http://www.microsoft.com/security/scanner/) For a lot of data regarding antispyware software, visit the subsequent Microsoft net site:
      http://www.microsoft.com/protect/computer/spyware/as.mspx (http://www.microsoft.com/protect/computer/spyware/as.mspx)
   2. decision 1-866-PCSAFETY or decision 1-866-727-2338 to contact security support.

For locations outside North America
To obtain bug and security-related support for locations outside North America, visit the subsequent Microsoft net site:
http://support.microsoft.com/common/international.aspx?rdpath=4