If anyone receives this error when trying to access OWA on Exchange 2007, and have modified their logon.aspx and/or logoff.aspx files (and probably any others), make sure the permissions are set correctly!

I was getting a blank page when trying to load OWA after updating to Rollup 3 for Exchange 2007 SP1 which I discovered was due to my modified logon/logoff files not being updated properly, so I reinstalled it and all was fine – until I re-applied my modifications.

Although the permissions looked correct at first glance, there definitely was something wrong with them as the 440 Login Timeout error disappeared once I toggled the allow inheritable permissions to propagate setting, removing all previously existing permissions in the process.

From a quick search on Google, there did seem to be a few other reasons you might be getting this error, but for me, resetting the permissions on all the files I had changed fixed it.

Hope this helps!