Error message when you install or start an MS-DOS or 16-bit Windows-based program One moment please... Although attempts are made to make the information in these bulletins accurate and understandable, they are only a guide. Any time you are making changes to Power Broker or to Windows, there is a chance of things going wrong. If you feel something is beyond your abilities or just not quite clear, contact our technical support department or get someone with computer experience to help you. November/2004 This is a Microsoft Windows issue.  This document is only a notification of what has happened and to be used only as a guideline.  Speak to your Microsoft Windows Vendor or a local technician for further details other than the ones outlined in this website document.  This issue may occur if one or more of the following files are missing or damaged. autoexec.nt config.nt command.com Note: So far, Autoexec.nt is the only file that has been reported from our Power Broker customers as being deleted.  Config.nt and command.com have not reported as being deleted. Error Message 16-bit MS-DOS Subsystem path to the program that you are trying to start or install C:\Winnt\System32\autoexec.nt,config.nt,command.com     The system file is not suitable for running MS-DOS and Microsoft Windows applications. Choose 'Close' to terminate the application. Click here for Microsoft's help document: http://support.microsoft.com/default.aspx?scid=kb;en-us;324767 This message has recently started to appear based on two known reasons:  Reason 1 The first is the recent Windows XP Service Pack 2 upgrade offered by Microsoft.  In some cases, Service Pack 2 deletes the autoexec.nt file.  Restoring the file from the method noted on the website link above has resolved this problem.  It has also been noted that an alternative method is to copy the autoexec.nt file from the c:\windows\repair folder, and pasting it to the c:\windows\system32 folder.  Shut down and reboot the machine and open Power Broker. Reason 2 The second reason has been reported that a recent virus/adware/trojan/highjacker program has deleted this file/files.  Restoring the file from the method noted on the website link  above has resolved this problem.  Unfortunately, should your computer have a malicious culprit that re-deletes this file, you will need to restore the files again.  Make a backup of the three files before you reboot so you do not need to use the CD again. Summary Either way, with both resolutions, you should shut down and restart your computer, and then check and see if the autoexec.nt file is still in your c:\windows\system32 folder or did it get deleted again.  If it's been re-deleted, you should contact someone in your local area to help you resolve the problem your having with the virus/adware/trojan/highjacker program that's infecting your computer. If you just recently installed Microsoft Windows XP Service Pack 2, and restored the file from the cd, and have rebooted and the autoexec.nt is still there, then rest assured that your problem is fixed. January 2005: A package called AdStatus Service or Server removes this file