0F6

Explanation
During processing of a SETEVENT macro for the generalized
trace facility (GTF), an error occurred. Register 15 contains a hexadecimal
reason code that explains the error: Code
Explanation
00
The issuer of the SETEVENT macro was not authorized through the
authorized program facility (APF), was not in protect key 0-7, or
was not in supervisor state.
04
The parameter list passed to SETEVENT was incorrect.
08
An incorrect address for the monitor call queue element (MCQE)
was passed to SETEVENT.
0C
The MCQE at the address passed to SETEVENT is incorrect for the
function requested.
20
The call to SETEVENT: Attempted to add elements to an existing event directory
Would have resulted in multiple MCQEs.

System action
The system writes messages and a dump.

System programmer response
If an installation-provided program
issued the SETEVENT, ensure that the program is authorized.  Correct
the error indicated by the reason code.  Run the job again.
If
an IBM-provided program issued the SETEVENT, collect all printed output
and output data sets related to the problem. Search problem reporting
data bases for a fix for the problem. If no fix exists, contact the IBM® Support Center. Provide the
SYSOUT output and the dump for the job.  

Source
Generalized trace facility (GTF)