Chris P

That's why I suggested putting the emails into a separate queue. The point is to not re-open solved tickets unless they need to be reopened. The dedicated queue would be checked just like any other queue.

My idea:

When I Solve a ticket with a comment, the email that's sent to the customer should clearly state the ticket is closed and any reply would be added to the ticket history but not reopen it. If they want to reopen the ticket they need to click a button/link.

"This ticket is considered resolved. If you need additional assistance or feel this ticket was closed prematurely, please _reopen it_."

A simple reply to the email will not reopen the ticket. It could potentially put the ticket into a queue of some kind but not reopen it by default.