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Check with your institute that your account is active, then use "forgot password" on the login page.
Go to loginContact
The most useful first message says what you teach, roughly how many students you have, and whether you already use GIMS. We will reply with what setting up would look like for you.
Already using Classroom?
Accounts are created by your institute, so a password reset, a missing course or a wrong batch is fastest to fix there. If your institute uses GIMS, the same email and password work here.
Check with your institute that your account is active, then use "forgot password" on the login page.
Go to loginEmail us with what you were doing and what you saw — a screenshot helps more than anything.
Tell us the problem rather than the feature. That is usually a better conversation.