RDP windows 7 credentials are invalid?

Question

Windows

Windows 7 maximum sp1 I
did everything, created an admin user with a password and added it to the group for rdp.
There is no domain, the connection is on itself through an external internet ip with forwarded port 3389 on the router.
I enter the form
\username
pass
I get a refusal
credentials are invalid

Answer 1

pc name\account
password