Hi,
It's really odd, we had the same issue last week with another member., I am not sure what's going on to be honest.
can you confirm the following:
-- what Unity version
-- what playmaker version
-- Did you get PlayMaker it from the asset store of hutong games store?
-- you install PlayMaker on a fresh empty project right?
-- normally, Unity api updater must run with a dialog box asking to confirm this, can you double check it does?
Bye,
Jean