Thanks, but that just takes me back to searching a forum, which is useless. Since installing LR CC 2015.10 today from LR CC 2014 I've had several new issues and can't figure out how to get things fixed. If you have some ideas, here's what's going on.
1. Can't import MP4 video now, worked yesterday on older release.
2. I was using LR 5.7 for one catalog, after the update I can't use that any longer and was forced to upgrade that catalog to this new release.
3. Takes significantly longer on file import to display the thumbnails for the images
4. Saw a suggestion for #1 above to purge the video cache in the preferences setting and re-open LR. Let the purge function run for over 5 minutes to purge 3GB and when it never finished in that time I cancelled it. 10 minutes later it's still trying to cancel and hasn't finished. I now need to cancel LR in task manager.
It's a frustrating day in LR Adobe land.