Hi, I have the same issue, I've changed the ps_mbo.php I've deleted all the folders in var/cache, and after doing this I still have the same issue :
"You have requested a non-existent service "mbo.tab.collection.provider"."
And if I change the ps_mbo foder to ps_mbo.bak it works but I can't access to the module manager in the backoffice.
How can I solve this please ?