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Computer Technology

When Windows Won't Boot
If for any reason Windows does not start normally, you should try to start it in Safe Mode, which bypasses the real-mode drivers and configuration to load a very minimal protected-mode configuration that disables the Windows drivers and a VGA display.
However, if Windows will not start in Safe Mode, one of the following conditions is likely the cause:

      The PC is infected with a virus: Install and run an anti-virus program on the PC.

      The CMOS settings are wrong: If you can access the BIOS setup program and the configuration data, check it for accuracy. Hopefully, you have a paper backup of what the CMOS settings should be. If not, you may need to contact the manufacturer.

      There is a system resource or hardware conflict: Check for IRQ conflicts, duplicated COM ports, PCI BIOS settings, and possible defective RAM.

      MSDOS.SYS has an incorrect setting: Verify that there are no incomplete or invalid settings in this file.

      A DriveSpace drive cannot mount a compressed volume file (CVF): Follow the procedures in the Windows Help files for CVF files and troubleshooting DriveSpace.

      There is a registry errror: Boot to the command prompt only startup option and run SCANREG from the command line prompt.

When all else fails, reinstall Windows into a new folder to determine if the problem is something left over from the previous operating system or Windows version.

If Windows will boot to Safe-Mode, you should step through the startup process using the selective Startup option of MSCONFIG (executed from the Start Run box) to try several different startup options.