OWA timeout for Exchange: how to increase it
Posted by Wes in 
Using the webmail interface for Exchange is super handy for users at home or on the road. However, I received several questions about being logged out and having to continually log back in.
First, you have the option to select that you’re logging on from a “private” or “public” computer. The default for “private” is 20 minutes, while the default for “public” is two hours. If you log in at home on a weekend and are checking back every-so-often, this might be a pain because you’d be timed out every two hours.
So, I poked around to find the setting that controls this. Turns out there are registry keys for both of the values that you can modify.
Browse to HKLM\System\CurrentControlSet\Services\MSExchangeWeb\OWA\ and you’ll find two keys:
- PublicClientTimeout – timeout when someone picks public (default of 20 minutes)
- TrustedClientTimeout – timeout when someone picks private (default of 120 minutes = 2 hours)
I suggest changing this to 1440 (for 12 hours) or 2880 (for 24 hours) so users can stay logged in longer.
