You'll recall our earlier story on registry corruption for certain users upgrading to Windows XP SP3. The cases of registry corruption seemed to have a common thread: Symantec security products. Originally Symantec blamed Microsoft, but in a post on a Symantec support forum, a a senior manager with Symantec indicated the fault may indeed lie with Symantec's products.
"After a lot of testing, we've reproduced a number of different cases
where applying the XP SP3 upgrade adds additional registry keys within
already-existing Symantec registry keys," said Anschultz. "We have
determined that the SymProtect feature is involved, though this issue
is not exclusive to Symantec customers. To help prevent this issue from
occurring, you should disable SymProtect prior to installing the
Windows XP SP3 upgrade."
Symantec also noted they would post a standalone tool later. However, a later post on the same thread
seemed to indicate a similar issue with the installation of Vista SP1,
although that same Symantec manager noted they hadn't noted such
reports previously.