The only thing you could do is set up ATS to allow creating tickets by email. If the user sends an email to that address from the email address you have for them on file in their user account a ticket will be created for them.
Beyond that, we'd never do ANYTHING in the web interface to bypass the need for logging in because that would be a MASSIVE, GLARING SECURITY ISSUE. If I know your email address I come to your site and file a Guest ticket pretending to be you. I can copy your writing style and attach / link to malware to the ticket. Your staff sees that the ticket is filed by you, they trust you and they follow the instructions on the ticket. Their machines are now infected with malware.
How does that differ with sending an email? Well, the email server will reject emails sent with a “fake” email address because of SPF mismatch at the very least. That is to say, if I try to use my mail server to send your site an email with the From address set to your email address your server will reject it because it will see that the mail exchange server that sent the message is NOT in your domain's SPF allowed list. As a result my message never reaches your site's ATS and I can't spoof an email from you.
If you cannot implement that there are, of course, some alternatives. If someone has a problem logging into their site they should be using the Joomla account recovery tools (forgot your username, forgot your password) or if it's a Two Factor Authentication / Two Step Verification issue they could use the contact form on your site. That's what we do on our site. We then ask people to reply by email from the email address we have on file or, if that is not possible, to provide a form of photo ID where they can cover everything except their photo, name, surname, last 4 digits of the ID number and the issuing authority.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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