What is your setup? ActiveSync version? PDA? Desktop OS?
I did experience that scenario with an older version of ActiveSync one time. Never got to the bottom of it so I just reinstalled and it corrected whatever the issue was. Have you tried manually selecting "Get Connected" so you can create a partnership?
How many computers has the PocketPC partnered with? There is a limit (2). After that, it goes into guest mode until you get rid of one of the existing partnerships. Also helps to make sure that the versions are the same on the PocketPC and the host.