Hi, below is what my Autoexec.bat looks like. Is this from some kind of virus trying to scare me? Ü+/  î %File allocation table bad, drive %1 Invalid COMMAND.COM BEnter correct name of Command Interpreter (eg, C:\COMMAND.COM) >> Terminate batch job (Y/N)?Cannot execute %1 Error in EXE file "Program too big to fit in memory  No free file handlesBad command or file name Access denied  Memory allocation error& Cannot load COMMAND, system halted ! Cannot start COMMAND, exiting . Top level process aborted, cannot continue  Cannot find File DLL - %1  Write protect errorInvalid unit Not readyInvalid device request Data error!Invalid device request parameters Seek errorInvalid media typeSector not foundPrinter out of paper errorWrite fault errorRead fault errorGeneral failureSharing violationLock violationInvalid disk changeFCB unavailableSystem resource exhaustedCode page mismatchOut of inputInsufficient disk spaceToo many parametersRequired parameter missingInvalid switchInvalid keyword $Parameter value not in allowed rangeParameter value not allowedParameter value not allowedParameter format not correctInvalid parameterInvalid parameter combinationInvalid functionFile not foundPath not foundToo many open filesAccess denied Invalid handleMemory control blocks destroyedInsufficient memoryInvalid memory block addressInvalid EnvironmentInvalid formatInvalid function parameterInvalid dataMemory allocation error& Cannot load COMMAND, system halted ! Cannot start COMMAND, exiting . Top level process aborted, cannot continue  Cannot find File DLL - %1  Write protect errorInvalid unit Not readyInvalid device request Data error!Invalid device request parameters Seek errorInvalid media typeSector not foundPrinter out of paper errorWrite fault errorRead fault errorGeneral failureSharing violationLock violationInvalid disk changeFCB unavailableSystem resource exhaustedCode page mismatchOut of inputInsufficient disk spaceToo many parametersRequired parameter missingInvalid switchInvalid keyword $Parameter value not in allowed rangeParameter value not allowedParameter value not allowedParameter format not correctInvalid parameterInvalid parameter combinationInvalid functionFile not foundPath not foundToo many open filesAccess denied Invalid handleMemory control blocks destroyedInsufficient memoryInvalid memory block addressInvalid EnvironmentInvalid formatInvalid function parameterInvalid datanvalid media typeSector not foundPrinter out of paper errorWrite fault errorRead fault errorGeneral failureSharing violationLock violationInvalid disk changeFCB unavailableSystem resource exhaustedCode page mismatchOut of inputInsufficient disk spaceToo many parametersRequired parameter missingInvalid switchInvalid keyword $Parameter value not in allowed rangeParameter value not allowedParameter value not allowedParameter format not correctInvalid parameterInvalid parameter combinationInvalid functionFile not foundPath not foundToo many open filesAccess denied Invalid handleMemory control blocks destroyedInsufficient memoryInvalid memory block addressInvalid EnvironmentInvalid formatInvalid function parameterInvalid dataer missingInvalid switchInvalid keyword $Parameter value not in allowed rangeParameter value not allowedParameter value not allowedParameter format not correctInvalid parameterInvalid parameter combinationInvalid functionFile not foundPath not foundToo many open filesAccess denied Invalid handleMemory control blocks destroyedInsufficient memoryInvalid memory block addressInvalid EnvironmentInvalid formatInvalid function parameterInvalid datalid handleMemory control blocks destroyedInsufficient memoryInvalid memory block addressInvalid EnvironmentInvalid formatInvalid function parameterInvalid dataryFail on INT 24Too many redirectionsDuplicate redirectionInvalid passwordInvalid parameterNetwork data fault!Function not supported by network'Required system component not installed

did you start chkdsk or scandisk sometime? if it found lost clusters and your repaired it, that can happend if the clusters with the autoexec are included that this append, delete it and create a new one

It looks like it has some of command.com in it. I don't think this is virus activity as much as a scambled FAT from a crash. Run scandisk and I bet you have crosslinked files. You might find you need to reload command.com and other startup files. Have a boot diskette ready before running scandisk

If FAT was scrambled, then why would it still boot OK? I using the PC right now. I tried command.com that was on my computer, put it on a boot disk and put it on a 8086 CPU computer and it booted fine. It started this after I installed something. But I forget what I installed.

if the programs that are nessesary are okay, you can boot autoexec is not nessesary you only need io.sys, msdos.sys and command.com

Yes, you may be better off without autoexec.bat 'cos it sure looks a mess. It's only necessary for DOS programs (such as games). I appreciate that you may want to run these of-course. DOS faulting will still work without autoexec.bat There are some virus checker programs that have a line for doing boot scan (eg AVG & Norton) in which case you obviously need that particular line. By the way config.sys is only used for DOS programs and Windows runs fine without this too.

Yeah delete it. Looks like it got crosslinked with lines from some other file. It boots OK because they aren't executable commands. The run scandisk.