Pages are not opening

Hi Team, Recently we have upgraded project from Mendix 4.5.0 to 5.12.0 version. After upgrade most of the pages that are opened using microflows/java actions are not opening. A progress bar is shown but the pages are not loading. We dont see any errors in Console also. Kindly help.
1 answers

One thing could always be that the security settings aren´t set properly. Then Mendix tries to retrieve data from the database, but is prohibited by for instance entity access not being set properly. In my experience this doesn´t give feedback to the end/user that rights aren´t set properly and results in the progressbar appearing and the page continuoulsy looking like it is loading.

Are there maybe extra modules/MF's added / modules/MF's renamed during the migration?