When a workflow is started manually a promptset appears, everything works as designed, the promptset shows and runs.
Also it runs via a schedule object normally.
However, when clicking restart in the schedule object where the workflow belongs to, the promptset does not show, and the task gets stuck in waiting for user input.
At the same time force traces and a UC4Dump file is generated in the temp folder of the engine as one of the wp (ucsrvwp.exe) crashes during this operation.
On the file UC4Dump_AENAME#WP0XX_DATE_OF_THE_DUMP.txt this kind of message appears:
20250107/112550.724 - Access violation at 00007FFAD28EA6D0 on read 1936391058552
The analysis of the minidump file generated would show that the crash had occurred due to a sentinel one library (InProcessClient64.dll):
Automation Engine 21.x or 24.x on Windows with Antiviruns Sentinel One running.
Third Party: Sentinel One would interfere with the automation engine process (ucsrvwp.exe on this case) in case of important load as during the calculation of the prompsets when the workflow within the schedule object was restarted.
Add an exclusion to the Automation Engine binaries folders in Sentinel One, setting them in Performance focus to prevent False Positives like this one.