floppy drive and usb pocket flash drive problem

When I try to read from either of these drives i get an
error message saying 'this disk is not formatted - do you
want to format it now'. I don't want to format these
drives, but even when i tried to use drive a: to format a
blank floppy i received another message saying the format
could not be completed. Operating system is windows XP.
Device manager reports that the drives are functioning
correctly.

(I don't know if it's a related problem but while I can
read from and write to the hard drive I cannot run
defrag.)

I've seen a number of similar problems posted - but no
solutions. Can anyone help?

Alastair