If you are running Windows 95, Windows 98, or Windows ME and are using Share Level Access, you may have a vulnerability that exposes you to an attack that is able to acquire full access to your hard drive.

If your operating system is any of the following please click on the appropriate link below to update your software.

Download locations for this patch

• Microsoft Windows 95
  http://download.microsoft.com/download/win95/Update/11958/W95/EN-US/273991USA5.EXE
• Microsoft Windows 98 and 98 Second Edition
  http://download.microsoft.com/download/win98SE/Update/11958/W98/EN-US/273991USA8.EXE
• Microsoft Windows Me
  http://download.microsoft.com/download/winme/Update/11958/WinMe/EN-US/273991USAM.EXE

One effect of having this vulnerability is the possible infection of your machine with the w32.opaserve worm.
You can tell if you are infected by the presence of the scrsvr.exe, macro!.scr, or alevir.exe file on your computer. These files may be marked as hidden or system files, so be sure you change the properties under Folder Options to allow viewing these files.
 

Other update sites and repair tools

• If you have Microsoft Windows 98 or later get the latest critical updates at
  http://windowsupdate.microsoft.com
• To clean the "w32.opaserve" worm download and run the file at
  http://securityresponse.symantec.com/avcenter/FixOpsrv.exe (Note: This tool did not detect the macro!.scr file in some cases. This file was called from the registry under the key HKLM\Software\Microsoft\Windows\CurentVersion\Run\cronos)
  For more information on the cleaning tool view the Symantec site at
  http://securityresponse.symantec.com/avcenter/venc/data/w32.opaserv.worm.removal.tool.html