When I starting up machine I get this message from DOS black screen:
Invalid settings in the MSDOS.SYS file: ORIG_DIAG_BOOTMENU=<NIL>
This machine is unstable. Sometimes I can proceede and boot to Windows 98 but another time it hangs at Windows 98 screen so I have to power off and go to Safe Mode.
This machine uses 3 serial ports.
What could be wrong and how I could go about fixing this problem?
(I am not knowledgeable in DOS)
Thanks for help.