Error Message :
N/A

For some of the Server Processes, the two columns "MQ-set (own)" and "MQ-set (active)" are not showing any values. 
This affects WP's as well as DPW's.

<Please see attached file for image>

The DWPs no longer show any MQ-Set values in the system-overview.

An error has been fixed where a Zero Down Time Upgrade (ZDU) does not work if DWPs of the base version are active at the beginning of the upgrade procedure.
DWPs are not allowed, but the old DWPs remain as DWP, which causes the error. Logging in is no longer possible. 

Cause type:
Defect
Root Cause: During ZDU, DWPs are not permitted. Yet newly started WPs become DWPs. As a result, logging in is no longer possible, because DWP messages are written to wrong MQDWP.

OS Version: N/A

Update to a fix version listed below or a newer version if available.

Fix Status: Released

Fix Version(s):
Automation Engine 12.1.0 - Available
Automation Engine 12.0.2 - Available
Automation Engine 11.2.5 - Available

Workaround :
Before ZDU process starts, check DWPs. All DWP roles must be manually changed to WP.