Thx all,

the error messages are clarified now.
After a while it is pretty clear that the printer sharename used in my script is not working (\\\)
Itīs clear now that the can not work properly!! Itīs just luck which Domain Controller is answering the request from the client as each DC may reply due to the default DNS entires. My fault, not script related.

On the the script developemtn I will work on the next days, depending on the time I can/have to spend on it.

Cheers.