i can add a new Hosting Organisation without any Problems.
But if i try to create a Mailbox i see this error below.
“Server was unable to process request. —> Error executing ‘CREATE_MAILBOX’ task on ‘corre corre (corre@corinna.de)’ EXCHANGE —> Server was unable to process request. —> Cannot process argument because the value of argument “userName” is not valid. Change the value of the “userName” argument and run the operation again.”
Someone any idea why this happen?
best regards and thanks

Answered question