1. Rename the member CTLIPROF from the user’s ISPF profile(USER.ISPF.ISPPROF) - At the next logon a new CTLIPROF member will be generated
2. Log back into Endevor and check that the panel can be accessed.
This is a workaround that will clean up Endevor variables and will cause the previous user defaults (CCID, comments, jobcard, etc.) to be discarded.