EndNote X6 on Windows 7 - Stalls when importing PDF files

Since I updated to X6 from X5, I haven’t been able to import a PDF file (let alone a folder). Attaching PDFs to existing references is not a problem, but importing them (when they have DOIs) is impossible. When attempting to, EN stalls and I always end up having to CTRL-ALT DEL the thing.

Any idea why?