I have exactly the same problem with the same update,msxml4-KB927978-enu.log, installed on the 17/11 at 22:52. It is showing as installed in Add/Remove programs and for some reason the log file? which in my case is in a folder named ce53395e9420f954ab9d5aa1e56c31 has gone to my external hard drive ‘E’. Can I just delete this folder and where do they normally go, if anywhere? How did it end up on my 'E' drive.
One final comment on this subject. Received a reply from MS help website:
"Found the following on : click here (You might have a look at the full thread)
Q :WHY did it write a log to my external drive? A :This is normal. XP will use for temporary storage purposes the connected drive with the most free space. It creates temporary folders named similar to yours ........ It usually cleans up after itself when done with Windows Update, but not always.
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