1. Log on to the Client Access server.
2. Start Registry Editor (regedit).
3. Locate the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchange OWA.
4. Create the following DWORD value if it doesn't already exist: ChangeExpiredPasswordEnabled. The value type will be REG_DWORD.
5. Set the value of ChangeExpiredPasswordEnabled to 1.
6. Exit Registry Editor.
7. Restart the IIS (iisreset).
