Hi again! I have one user reporting that her OWA log-in is not succesfull. The error message is: "The page cannot be found" "404" All the other users have no problems connecting to the OWA. Either on the backend directly nor through the front- end server the implicit login succeeds (http://server/exchange) When she logs-in explicit on the BACKEND (http://backendserver/exchange/useraccount) the login is successfull. I have checked the configuration of virtual directories and NTFS permissions. (KB327843) We have no URLScan installed. The server is also no upgraded 5.5 server. I also checked the OWA troubleshooting guide and found no issue concerning this situation. SMTP addresses for the user object are correct. Tonight I tried a server reboot. No log-in. What else should I check? Any ideas? Thanks in advance.