My PC seems to sync everything to Dropbox - its caused my storage to fill up with loads of thumbnails from various apps I use. There's currently 1,700 thumbnails stored which I need to get rid of. These all synched in March this year so I can hilight the month button and try and delete all. This is when Dropbox says its deleting 1700 files then says it can't. Is there another way that doesnt involve clicking small batches at a time???