and just to note:I tried to reproduce the situation on a test site:
- Joomla 5.4.10 with JEM 4.5.0, sample data and registrations;
- then upgraded to Joomla 6.1.4 with Upload & Update;
- then JEM 5.1.0 beta 5 installed over JEM 4.5.0.
On a clean site, the update works. The permission migration completes, and events can be shown and edited.
Your exact message appears when the Joomla permission tree itself (the
table) has an inconsistency. It does not have to be in JEM; one wrong entry of any extension is enough. Older sites often have such entries, for example left behind by an uninstalled extension.In that state:
- JEM blocks editing of events, categories and venues, as you describe;
- Continue permission migration stops with the same message.
The JEM data itself is not affected
