I just registered on Ebay and it generated a very useless user name.
So there is an option that you can change that user name: https://reg.ebay.com/reg/ChangeUserName
When I enter a basic name, I get a somewhat useful error (there are no alternatives at "below"):
When I enter some other name, I get another message:
When I enter some unique name, I get an exclamation mark...and no error message.
What does it mean? How should I know what to correct? This looks very lame...