DVD drive letters.

Now can someone help me.

I have 3 DVD drives on my PC. After a boot they occupy drive letters F:, G:
and M:.

Using the disk manager from My Computer I change them to be (respectively)
N:, L:, and M:.

However next time the machine is restarted, they revert back to
(respectively) F:, G: and M:.

This only started happening a couple of weeks ago. Does anybody know why
Windows (XP Home SP2) keeps reverting the drive letters (or by what
mechanism it can)?


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