Task Sequence OS Upgrade deployments not appearing in Software Center

Here’s a strange one. I was testing a Task Sequence to upgrade Windows 10 ConfigMgr clients to Windows 10 v. 1803. On one of  the test systems the Task Sequence deployment failed to appear in the Software Center. It was displayed in Software Center on all of the other test systems.  After digging through all of the usual logs and performing all of the tests to attempt to identify the issue, I came across an old blog post about applications, but not packages appearing in the Software Center in Configuration Manager 2012. The post suggested that if two or more users were logged into the system at the same time, only the user with the highest Session ID would see the deployment.

Sure enough, I checked Task Manager to see if anyone else was logged into the system, and another administrator had a disconnected session with a higher Session ID. I killed his session and immediately received notification that there was a new Operating System deployment available. An easy fix for a frustrating few hours of troubleshooting.