So I followed the instructions for the upgrade from XF1 to XF2. This is what pops up.
There are at least 1 file(s) that do not appear to have the expected contents.Reupload the XenForo files and refresh this page.Only continue if you are sure all files have been uploaded properly.
I'm having the same issue but it's "3 file(s) that do not appear to have the expected contents." I've downloaded the most recent zip archive from my customer area (15 mins ago).