If you get Error 80090308, “The token supplied to the function is not valid” when expanding the public folders in exchange 2003. Then use adsiedit.msc to do the following :-
Configuration >
Services >
Microsoft Exchange >
Domain Name >
Administrative Groups >
First Administrative Group >
Servers >
Servername >
Protocols >
HTTP >
1 >
Exadmin
right click on Exadmin and click Properties.
Find msExchSecureBindings and click edit.
Highlight :443: and click Remove.
Do a IISRESET. All good.