Error after upgrate to 1.5.4

I have just upgraded from 1.5.3 to 1.5.4, this is done using softaculous app installer. when I login in I immediately get a red screen saying:
An Error Was Encountered
The action you have requested is not allowed.

I have enabled debug but cannot see anything useful

Did you run the /setup after upgrade ?

yes i did and it all reported as OK

This has resolved itself, i think i needed to just wait