Symptoms
The OLEDB Provider for DB2 does not support user names with a length greater than 25.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Resolution
This issue is fixed in the following cumulative update for Host Integration Server:
Cumulative Update 1 for Host Integration Server 2020
References
Learn about the terminology that Microsoft uses to describe software updates.