Note: You are currently viewing documentation for Moodle 2.8. Up-to-date documentation for the latest stable version of Moodle may be available here: error/moodle/invalidconfirmdata.


From MoodleDocs

The usual reason for this error message is that you have waited too long before clicking the link in the account confirmation email. By default, any unconfirmed accounts are deleted after 7 days.

Thus you should try signing up again, and this time click the link in the account confirmation email straight away!