KB ID 0000437
Problem
Note: This also works with Exchange 2007 SP3.
If you have a user password that has expired, or you have set the password to be changed at next logon, then this can cause your remote users a problem. Providing they have access to OWA, they can now (Post Exchange 2010 SP1) reset the passwords themselves.
Note: It is possible to log in with an OLD PASSWORD when accessing OWA this will happen for approximately 15 minutes (Special thanks to Jason K. Roberts). For more information see,
An old password still works after you change it in Outlook Web Access
Solution
Essentially a quick registry change on your Exchange server, then re-start the IIS Admin service.
Related Articles, References, Credits, or External Links
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