The following steps can be used to increase the timeout of the Defender Management Portal:
1. Open IIS Manager on the server running Defender Management Portal.
2. In the Connections pane, expand the server node and click Application Pools.
3. On the Application Pools page, select the Defender Web Interface pool, and then click Advanced Settings in the Actions pane.
4. Under Process Model, type number of minutes in the Idle Time-out (minutes) box and then click OK.
5. Restart IIS service or Defender Web Interface Application Pool.
If you have modified the timeout value in the Defender Management portal web config file (C:\Program Files\One Identity\Defender\Management Portal\WWW\Web.config) then you will also need to update the below timeout value in the web config file:
<authentication mode="Forms" >
<forms name="DEFAUTH" loginUrl="~/WinLogin" cookieless="UseCookies" timeout="50" slidingExpiration="true" />
</authentication>