If you're logging in with the same Redgate ID each time you install your license on a machine then you will never run out of activations as this only uses one entitlement. If an additional user activates, using their Redgate ID, this will consume another entitlement.
If you are having problems activating your license on a new computer you may need to log in to the customer portal and free up an activation by removing an old user who is no longer using the license. You will need to contact the license owner/administrator if you can't see the license in the portal.
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