To login to an existing mapped project in the Package Explorer view, right click, and select Team->Logon to SCLM. Alternatively, in the SCLM view either click the Logon to SCLM icon, or if you have already populated a project you can right click and select Logon to SCLM.
The logon function allows you to supply your user credentials for an SCLM location. When you initially connect to a project for SCLM management, an SCLM server address is required. If you map any further projects to the same server location, those credentials are used. If you want to map a project to another SCLM server location, you are prompted for your credentials for that location.
User credentials are session-only attributes and must be re-entered for each session access. If you do not access a particular location during a session, there will be no need to enter your details for that location.
The logon dialog consists of User Name and Password fields, and the Change password checkbox.