For few ICEM files, especially big or complex ones which probably contain a lot of polygons, the ICEM conversion may stall. Additionally, the load ICEM license is not handed back to the license server, causing the next user in line to be denied a license and instead being presented with a “license not available” error.
Manually end the rttct.exe process using the task manager. It is also possible to create a batch file containing the command
taskkill /f /im rttct.exe
This ends the hanging rttct.exe process and returns the license to the licensing server.