win98/2000 dual booting

This can be caused by a number of things which to check for

The setup is trying to access the floppy to boot from,check the drive configuration in BIOS setup and see if you have the A:\drive as the first boot
device,change to C,CD-ROM,A

Checkto make sure that floppy cable orientation is set to pin 1 correctly and that drive is working properly

Check the hard drive for any noises and run scandisk for bad sectors (this can be done using the startup disk from command prompt) on the drive,drive could have bad sectors or going bad

Boot into Safe Mode and open Device Manager and make sure that the Disk Controller does not have an exclamation mark

This can be caused by a number of things which to check for

The setup is trying to access the floppy to boot from,check the drive configuration in BIOS setup and see if you have the A:\drive as the first boot
device,change to C,CD-ROM,A

Checkto make sure that floppy cable orientation is set to pin 1 correctly and that drive is working properly

Check the hard drive for any noises and run scandisk for bad sectors (this can be done using the startup disk from command prompt) on the drive,drive could have bad sectors or going bad

Boot into Safe Mode and open Device Manager and make sure that the Disk Controller does not have an exclamation mark

if you are using a scsi interface for your hdd, you need to install the latest scsi driver. During win2k setup, press F6 to load scsi drivers. Normally, boot device inaccessible problems happens because either the os cannot access your hdd through your controller, or you have a different driver installed in your win2k os. Normally, I always reproduce this kind of error when i transfer an hdd from one pc to another with a different motherboard.

hope this helps.