This is not an official letterhead for a person in uni.

1. Ususally in such a letterhead there is a Uni-logo.
2. no name of the department
3. Email address is a private email address.

So it is just a private letterhead.
Even as a private letterhead it is not suitable
4. his address should be on the right.
5. It is Milchstr., not milchstr.

What a joke it is!