You need your JACOBS domain user account. This is the CampusNet user name, and the CampusNet password.
If you don't know your CampusNet credentials, please see here: log-in to CampusNet.
The computer to logon with the JACOBS domain account has to be member of the JACOBS domain. If the computer is a standard installation from IRC-IT, it most likely is. If the machine was setup by someone else or based on specific requirements, it isn't.
If it isn't, you can't.
Login to a print server for printing does not require the client computer to be part of the domain.
The domain name is JACOBS
See JACOBS domain for more information, esp. on how to reset passwords.
On a Microsoft Windows login screen you have to enter only your CampusNet user name and then have to choose the domain from the drop-down box.
Don't use the local machine "domain"
Within the drop down box, the name of the computer you are trying to login to appears. Do not use this entry! Use JACOBS!
Sometimes, e.g. if using a non-JACOBS computer to access network shares, you have to specify your name as DOMAIN\USERNAME, known as Windows domain notation.
An alternate syntax to write the login name in such a case is USERNAME@jacobs-university.de, known as Kerberos notation.
Hence, if your account is jsmith, the notation of your username is either JACOBS\jsmith or email@example.com.
If you are logging in to a Windows machine, at the login prompt, your username is jsmith, and from the drop down menue below select JACOBS as the domain to login to.
Don't confuse this with your email address
Just because there is an '@' sign in the Kerberos notation of your domain name does not mean, that it is an email address. You can not login with your email address.