You want to erase an application from your STM32-Primer? Here is the real syntax, using circle_mgr.exe:
First run
to list the applications present on the Primer. You will know their exact title. Then, you find out that the application you want to erase is called MyApp. So you can execute:
Here it is, the app is removed from the Primer and the CircleOS FAT table is updated.
Finally, to restart the CircleOS, type
Lionel