Roaming Profiles affected after windows updates

Hi
I have roaming profiles set up on windows 2003 server. When a person logs
on to their PC their entire profile is copied from the server to the local
Cocuments and Settings folder and when the user logs off the local profie
is copied back to the network. The users all have POP3 accounts, therefore
their pst is included in the roaming profile. This was working fine until the
end of October when new windows updates were installed. When a user logged
on to their PC in the morning, they had lost all emails from the day before -
it had reverted back to the pst from the day before. And It appears that
the profiles did not synchronise when the user logged off. The user also
could not get into any https websites. I scanned for viruses and spyware but
it didnt find anything. I had to create new users to overcome this problem.
Has anyone else had a problem with windows updates from the end of October?
or have any other explanation as to why this happened?
Thanks
Sinead