Microsoft is retrieving information from Exchange

[Leslie]

I have a user who states that from time-to-time when he
is composing an email, he gets the message "Microsoft is
retrieving information from Exchange." His computer will
stall for a minute or so and then he can continue. I
have not seen the message, so I'm not sure if the wording
is correct. Has anyone seen anything like this? Could
it be related to Send/Receive or Synchronization settings?

Thanks,

Leslie