I have a laptop, which was formerly installed with Windows 2000, and decided to downgrade it to Windows 3.1 (please dont ask why). However, this laptop will display the error message "Invalid system disk. Please replace then press any key." whenever I do not have a DOS 6.22 boot disk in, or I have the CD-drive in. Now, begin able to boot the computer without boot disk is very important to me, because having an old laptop means it cant carry floppy and CD-drive at the same time. And I need to have CD-drive in. And obviously it is not a good idea to take out floppy-drive while computer is still running.
The exact steps I took when downgrading my computer:
- Put DOS 6.22 boot disk in
- Restart and boot from floppy
- Type in FDISK
- Format entire hard drive
- Create new disk/partition
- Put in Windows 3.1 setup disk
- Install Windows to C:\WINDOWS\
- Oops! Forgot to run LOCK command first, so Setup fails
- Restart computer, boot from DOS 6.22
- Run LOCK command, locks the hard drive
- Restart setup
- Here we go again...
- Finally Windows 3.1 installs
- It runs fine
- Then I shut down computer to put back CD-ROM drive because I need to
- Start up computer
- Oh no! "Invalid system disk" error
- I put back in floppy drive, stick in the DOS 6.22 disk
- Oh my goush it works
- But then I realize theres a problem. I need CD drive!
- So I come to Computer Hope forums in search of an answer.
Some pieces of info that may help:
- When Windows 3.1 installed, it automatically set DOSPRMPT.PIF to point to A:\COMMAND.COM. hmmm.......
- Also, there was nothing in the root directory. No autoexec.bat, no config.sys, no nothing. hmmmmm........
Please help! Thx, smiley325.