Why do I get the error 'No privileges to perform this action' when I click on the invite email?

In Catalyst Authentication, this error occurs when you have already logged in to the application with a different account and try to confirm the password for another account from the invite email in the same browser window. The invite email contains a URL that opens a sign-up form where the invited user sets up their password. To resolve this issue, open the invite URL again in a different browser or with a different browser profile.

Refer to the Authentication Users Implementation help page for details on inviting users.