If you are seeing the above error, it can mean one of two things.
First, if you are trying to log into your admin area, you need to make sure that the url in you address bar contains /wp-admin/ at the end of it. The above login form is for your clients, not for admins.
Second, if your client is seeing this error, you may have forgotten to assign the portal to the client. Go back to your portal editor, scroll down to Client Accounts, and assign the portal to the appropriate client(s).
Once you’ve assigned the portal to your client, they will be able to log in without seeing the error.
