We have to two different designers, one that has been on 8.3 and another that was recently upgraded to 8.3. We were running into errors accessing the designer when it was 8.1, so after upgrading it to 8.3 it progressed further with opening the designer but now runs into a different error right before it actually opens the designer even though our other designer that has been on 8.3 has been working fine this entire time. Others who have had access to this designer have been and still are able to access it but anyone that was just recently given permission can't access that single designer at all. It first was saying I needed to update the designer to 8.3 but even after doing it multiple times it went from an error saying I needed to upgrade my designer (even though it already was) to receiving this error that I can't connect.
Try deleting your ignition cache..
I tried that already but it still runs into the same issue.
What does this mean - within Ignition, or at some IT level?
"Connection reset" virtually always implies networking/IT interference, not a (direct) Ignition problem.