OK, this may have nothing to do with XP, but I'm running out of ideas.  Problem:

I find that something is duplicating my folders.  The new folder has the same name 
as the old folder, except that the first letter has been removed.  The old folder 
is still there, and appears to be exactly as I would expect.  The new folder has 
nothing in it, but is Read Only.  If I remove the Read Only protection, the folder 
can be deleted, but will turn up again later.

The new folder will itself be subjected the same process.  This means, supposing 
I have a folder named "John", after a while I may find that I have, as a second folder 
named "ohn", then a third named "hn" as well as the first two, and eventually one 
named "n".  The first one ("John") will have all the contents I expect in there. 
 The other three will be empty, but Read Only.  Manual removal of any of the "phantoms" 
will simply lead to their re-appearance later.

So far this is only happening on my D: drive (where I keep most of my data files 
- excluding games (E: drive) big video files (F: drive) and driver, program, update 
etc files (G: drive).  The C: drive has the system and program and files, except 
for games).  "My documents" is reassigned to the D: drive, and the files which remain 
in "My documents and Settings" do not appear to be affected.

This does not happen to all the folders on the drive.  Neither the original folders 
nor the phantom folders are hidden and show up on both PowerDesk and Windows Explorer. 
 The D: drive is technically shared, but the only other user of the network at present 
makes no attempts to reach this computer.
 
I have a copy of Avira which is updated daily, and of Malware bytes and I've checked 
the disks with both of them.  

The problem has appeared since I starting using a new external hard drive, a Seagate 
FreeAgent XTreme, with automatic scheduled backup.  I thought that this process (and 
perhaps the Synch feature, which I ignorantly set up, thinking it a backup option) 
might be responsible.  However, a search of the Seagate forums, and of Google shows 
no signs of anyone else having this problem in connection with the Seagate software.

Repeated attempts on Google to find someone who has this problem, for any reason 
at all, throw up nothing, and none of the malware sites (eg sarc) seem helpful either. 

Has anyone else seen this behaviour before in any context, or has anyone any possible 
explanations?    

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