Can't seem to sync web and desktop version

Hi. Whenever I press the Sync button on my desktop Mendeley, I get the following error message: An unknown error has occurred, Mendeley has been notified. (EID: merr-522e50764d2ab) I also notice that some of the documents that I recently added to Mendeley Desktop are not showing up in my web portal, but that seems to be timed with the error message. Thanks for your help!