The most likely reason you received this message is that you are using another account for private purposes. 

This could be a Hotmail, Outlook, Xbox-Live, or Windows 8 account. If you are permanently logged in to another account or if your browser automatically saves sign-in data and you then attempt to sign in to UHRS, this is probably happening with the wrong account. 

The other account is not registered with UHRS and is therefore not recognized. Make sure that you are logged out of your entire private accounts and that your browser does not automatically enter account data in the login mask. 

You could also create your own user profile in your Windows, which you use only to work on UHRS jobs.