Licenses Not Returned to the Volume License Manager

Issue Details

When a client starts the NI application, a license is checked out from the Volume License Manager (VLM) server, and it is normally released once the application is closed. However, issues may occur when the application is not properly terminated.

For example, if the client machine is put into sleep or hibernation mode. In such cases, the license may remain stuck in a checked-out state on the server.

Solution

To resolve this issue, restart the Volume License Server through the VLM application on the server machine. This involves stopping the service and then starting it again. See how to Manage the Volume License Server.

After the server restarts and runs for about 1–2 minutes, any licenses that were stuck in a checked-out state will be released and become available again.

Alternatively, you can also free up the licenses by restarting the NILM License Manager service on the server, which you can automate easily using for example Windows Task Scheduler.

Additional Information

This problem can occur because when the license is checked out, the server receives a unique heartbeat from the client, and when the application closes, another heartbeat with the same unique ID will signal the server to free up the license. If the client computer goes to sleep or hibernate the heartbeat ID will change, so the signal to return the license with the original ID that was used to check out the license will not arrive to the server as the ID has changed. The server will see it is the same computer, so the client will not use another license, but the license stays checked out as the "return license" signal with the original ID does not arrive.