021

Explanation
A task management macro passed an address space
control block (ASCB) address with an error indicated in the following
reason codes: Code
Explanation
00
High order bits are set on in the input ASCB for move or add processing.
04
ASCBNOQ bit is off in the ASCB for add processing.
08
Attempt to add, move or delete the master scheduler address space.
0C
Acronym check for the input ASCB fails.
10
Incorrect CHAP entry function code.
14
Incorrect EXTENDED MOVE function code.
18
Incorrect EXCNT count passed from the system.
1C
Acronym check for the input enclave control block fails.

System action
The system abnormally ends the program that issued
the macro, writes a logrec data set error record, and writes a dump.

System programmer response
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
logrec data set record and the dump.

Programmer response
When calling the routine, ensure that the
high-order byte of the ASCB address is set to zero.  Correct the error.
 Run the job again.

Source
Task management