Server Not Found

Hi i am constantly trying to login in my app but every time i get this error"Server not Found" and also in the console i get OSGI event handler warning "EventAdmin: Exception during event dispatch [org.osgi.service.event.Event [topic=com/mendix/events/runtime/beforeRunning] | [org.osgi.service.event.EventHandler] | Bundle(webui [84])] (bundle: webui, service: [org.osgi.service.event.EventHandler])" and error "404 - file not found for file" I have recently upgrade my app from 4.5 to 5.12 and replaced collapsible panel from group box and snippet combination.
1 answers

The upgrade is probably the cause of your error. Did you migrate from 4.5 to 5.12 instantly?

Normally it's advised to first upgrade to the 'latest' release of Mendix 4 before upgrading to the 5 version.

I suggest upgrading to 4.8 (I think) first, before migrating to 5.12