Attempting to launch ArcFM Viewer for Engine results in the following error:
An ESRI license could not be checked out. This application cannot run.
One example of ESRI pop-up message.
Assuming an appropriate ESRI license is available, this error can be caused when the Auto-Check function is used in ArcFM Engine Administrator. Auto-Check can cause multiple ESRI product licenses to be activated. This can confuse ArcFM Viewer for Engine when it checks for an ESRI license.
In ArcFM Engine Administrator Layout and Licenses tab - Licenses, ensure that only Engine for the ESRIProductLicense is checked.