Originally posted by u wut m8:

The API has changed greatly and as such the plug in needs to be updated. Go to the Blender website and just re-download the previous version of Blender.

http://download.blender.org/release/

This page contains all of the older versions of Blender.

oh my god, your a bloody life saver! thank you!

so my blender just recently updated and I seem to have lost the ability to use both the source tools and my xps importer tools . . . is there a way to oh I don't know, revert it back to a previous version or is there an update planned or something?

edit: I should note I did in fact try to reinstall said tools but they were not showing up.

I am having the exact same issue . . .