If you receive a message from NTVDM, when starting an application, or from a service that there is no disk in drive A: or a CD-ROM drive letter, it may be that the path statement contains a reference to this drive. Check Control Panel / System / Environment and AUTOEXEC.BAT. This drive letter may also be referenced in an application shortcut. Lastly, if the drive letter is at HKEY_LOCAL_MACHINE\SYSTEM\SETUP\WinntPath, delete it and reboot.