CRC errors belong to a family of ominous disk-related messages which include Sector not found and the particularly scary Track 0 Bad -- Disk Unusable. Energetic troubleshooting notwithstanding, the offending floppy may end up in the bin, but don't give up too soon!
The CRC -- short for Cyclic Redundancy Check -- is a mechanism for checking the validity of data that is read from a disk. If the bits don't add up, after much clashing and grinding of the drive heads the system spits the dummy.
One common reason for CRC errors is a defective disk: if the data area of the disk has been damaged, read operations may fail, even if the directory structure is intact. Dirt in the disk drive can also lead to CRC errors. Since yours is a new drive, it's unlikely to need cleaning, but if the problem recurs with other disks it might still be worth spending a few dollars on a cleaning kit -- just to be sure.
Two other things you might try: first, scan the hard drive of your 286 machine with an up-to-date antivirus program. Then scan the problem floppy. Viruses routinely inflict all kinds of atrocities on (and via) floppy disks, and it's possible that your 286 has become infected while your other machines are still virus-free. Second, run a program such as Norton Utilities' Disktool against the problem disk. In many cases this will detect errors and correct a damaged disk.
- Neville Clarkson