RSF13004: System error [SYS%1: %2] occurred while releasing up channel idle semaphore for backend server '%3' in backend farm '%4'

Error code 13004
Error constant RSF_SERVER_FAIL_SIGNIFYING_UPCHANNEL_IDLE
Parameter 1 System error code
Parameter 2 System error message
Parameter 3 Backend server name
Parameter 4 Backend farm name
 Probable cause