I have Exchange5.5 on Windows2KServer and OWA on another Windows2KServer. Both servers in the same domain. My boss (his mailbox is approximately 1.3 GB) can use Outlook to use his mailbox, but when he try to connect to his mailbox through OWA, he gets this noticement: "OWA was unable to get to your inbox. To try to logon again, <http://home.evnit.evn.com.vn/exchange/logon.asp> click here. a For additional help on troubleshooting this problem, <JavaScript:openNewWindow('/exchange/tshoot.asp','inlineHelpWindow',600,500) > click here." I use Site Service Account to connect to his mailbox through OWA, but I also receive the same noticement. All other accounts work normally with Outlook and OWA. Can anybody here explain to me why and how to solve this problem. Many thanks in advance.