Getting Permission denied to access this portal.

Getting Permission denied to access this portal.

We have one user that can't login to projects even though access has been granted. This user can login to accounts.zoho.com but when login to https://projects.zoho.com/portals.do we get this error:

Unauthorized login to this portal

Permission denied to access this portal.
Check your portal URL again.


Sometimes we also get "server too busy".

We have tried killing sessions (in accounts.zoho.com) and we have deleted cookies; and tried different computers and still the same problem. All others use can login to the project except. We have also tried removing the user from the project and adding her back on; but still same problem.