Unintended Reboot on Update

[GLSchrader]

After checking for updates, the update dialog is presented and when some users initiate the update, the update begins the uninstallation of the old app and then stops responding. The update then has to be cancelled using the task manager. After it is closed, the old app is still present.

The user then has to uninstall the old app before running the install program for the new version of the app. When uninstalling the user is presented with a reboot checkbox on the final screen, even though that option was not included in the script. After installing the new version of the app, the user is again presented with a reboot checkbox, even though it was not included in the script.

This only occurs with some users. The vast majority of users are able to install the app, check for updates, run the update, and get the new app without having to reboot their machine. In fact, they are never presented with the reboot checkbox.

What could be causing this anomaly and how do I fix it?