My boss thinks there is a ghost on his computer.  He'll be working when
the computer will freeze for a second or two.  I don't find this all
that unusual.  There could be various things causing that.

But then he also notices that in his Outlook, the Send/Receive icon
down in the Status Bar "whirs" unexpectedly all the time when he's not
sending email and he didn't receive any new email in his Inbox.

Put the two together (I'm not convinced they are necessarily related)
and he thinks he's got a virus or spyware of some type, and keeps
asking me to fix it.

I have watched closely and have confirmed that his Outlook DOES seem to
do a Send/Receive when it shouldn't.  That is, he didn't receive any
email (there is nothing new in his Inbox and he has no rules diverting
anything to separate folders) and he definitely didn't send anything.

Our company has an Exchange server, so his Outlooks connects to it, but
for some odd reason he stores all his email on his own computer instead
of on the server (I think he's a little paranoid about all his data,
but I don't think he realizes that as domain administrator I can see
all his files anyway if I really wanted to).

In any case, I have watched carefully and have not seen anyone else's
Outlook behaving the same way.  All computers have the same version of
Outlook and connect to the same Exchange server.  The only difference I
know of is where the emails are stored -- he is the only one that
doesn't store email on the server.

I'm not convinced that anything is horribly wrong.  I suppose it's
possible some sort of malware is using Outlook to send out emails or
something like that, but his HijackThis log comes up clean as far as I
can tell.  I haven't ran any spyware scanner like ad-aware yet.

On the other hand, I can't explain Outlook's behavior.

Any ideas on what could be causing this?  Any way to track down or
monitor exactly what is happening?

Thanks!