What is the complete HDD & Optical drive configuration on your pc? It's normal to have C as the system drive & D as the first optical drive.
In addition to the info Fruit Bat/\0/ has pointed you to, my observation is that should you be running XP you will may problems running repairs under system file checker (sfc) if files need replacing as Windows Registry is set to look in D drive by default.
My HDD is partitioned as C & D. My second HDD, which is by far the largest, is E drive. CD & DVD drives are (usually) F & G.
I am a little reluctant to redesignate HDD E because it also contains some program files and none of them will work! I will have to re-download these programs. That's what I am trying to avoid, but if it has to be done then I will.
Does this help any?
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