Probably an old dll somewhere that is messing with you. Might be an old Episerver dll, old addon or old third party dll.
I would start removing all dlls that isn't part of alloy template site of the same version until I found the one...
Thanks for your input. I tried it but it did not fix it.
I compared all the versions of the relevant .dlls and they were exactly the same as the alloy (which was updated to latest packages through nuget.
Any other suggestions?
My guess is also that there are a something referencing to/depending on an old version of an dll.
I found an old thread with the same exception but with another property that might point you further:
I updated my client Episerver CMS site from that was on update 51 to update 82 through nuget console. It updated the dependant core files and everything was installed/updated successfully.
Although, when I try to launch the site I get an error message on the yellow screen stating 'RequiredAccess' property specified was not found. A more detailed error message can be found below.
The episerver log isn't showing anything, so I suspect that the eventlogger isn't even intializes before the error occurs.
I tried searching for the property "RequiredAccess" in my solution, but it returns 0 results.
I tried updating all the packages in the solution to the newest, but still receive the same error.