|Judago, aegis1, and wanderer,|
Thank you all for your quick replies. I'm sorry for the delay in responding but I had a dental implant yesterday and wasn't in a state to do anything. I appreciate the your taking the time to help out.
After I had posted my problem a friend gave me a fourth solution which was to use FDISK to assign a label to the rogue primary partition so I could then confirm my intent to delete it. In the interim, however, I had studied the MBR format carefully and concluded that to have a virgin disk, i.e., one large unallocated space, the Partition table in the MBR should be all zeros. I had no idea you would all answer so quickly (or, it being my first post, whether I had done it right and would get any answers at all). So with a courage born of "nothing left to lose" and my heart in my throat I used the Norton Disk Editor to manually zero out all the bytes from 1BEh to the signature at 1FEh in the MBR. It worked like a charm and I was then able to partition the disk properly,
Judago, in answer to your specific comments:
My system has two 80 GB physical hard drives, Disk1 and Disk2. Somehow Partition Magic, while working on Disk1, wrote something on it which causes programs (specifically FDISK, Norton Disk Editor, Partition Magic,and the XP Boot process to think there are 3 physical drives, Disk1, Disk2, and Disk3 on the system. Disk3 displayed as non-standard or, in the case of Partition Magic "BAD - Error 105" (improper cylinder boundaries). After I zeroed the partition table in the Disk1 MBR, however, Disk3 also became a clean (albeit imaginary) disk with one large unallocated space.
I understand the difference between physical drive and logical drive designation but the problem is that none of the programs involved will assign the alphabetical drive letters and so the system is unusable. The one exception is the XP installation process (as opposed to the boot process). When XP is installed from scratch in an empty primary partition the Setup program either ignores or overrides whatever Partition Magic did to Disk1 and assigns drive letters (i.e., C:, D:, etc.) properly. But it is very fragile. If I do ANYTHING (e.g., just switching the active bit and then switching it back, the system reverts to it's letterless status and is unusable.
As I have some urgent work to do I am "letting sleeping dogs lie" and using the system gratefully in its fragile state. In a couple of months after thing are not so critical I will try to figure out the Disk3 problem. Since I assume whatever Partition Magic did may be on Cylinder 0 I might try to zero it all after the MBR. If you have any suggestions I'd appreciate them.
I know it should be impossible to have a primary partition inside an extended partition but somehow whatever Partition Magic wrote on Disk1 caused all the programs to think that is what was there.
Since this was my first post I don't know if this reply is how to answer and say thank you and, if so, whether it goes to all of you
or whether I have to send three messages (how would I address them?) or even if I have to post a new top-level message. If one of you gets this I'd appreciate it if you could confirm that this is the way to do it.