The message “Another user is running this application in another session. This is not permitted under your licence.” is shown when the ADP software (TTService) detects that there are more than 2 users / logon sessions accessing the ADP data simultaneously.

This can be the Administrator who installed the ADP software or another user having logged on to the same PC without logging of the account when done. The error will typically also be triggered if the ADP software is installed on a server which several users connect remotely to, and do not log off their sessions after use.

The quick fix for this issue is to restart the PC to release any existing ADP sessions on the PC and then try to access the ADP again, however, the below points might be worth checking out to prevent the issue from occurring again.

Refrain from using "Fast User Switching" on PCs which are running the ADP software. This means that one user session can remain running in the background whilst another user logs on and uses the same PC.

In addition to this, the "Fast Startup" feature introduced in Windows 8 and newer are also known for causing issues with the TTService. The reason for this is that a system shutdown when having "Fast Startup" enabled will not clear existing ADP user sessions registered in TTService, so on the next log on, Windows will register an additional user session when accessing the ADP. We generally recommended to disable "Fast Startup" on PCs running the ADP software.