all video thumbnails replaced by gray icon, after iOS 8 update on an iPad2

This worked for me!!! I was so pleased to be able to see the Images and titles from my videos on my iPad Air again! Thank you. The process was pretty quick. Just went to Get Info and then under Options, changed from Movie to Home Video. The movies moved over with their covers as before. Thank you to Sjallum.

The thumbnail issue still is present on iOS 9.3.4. But based on the info in this thread coupled with some experimentation, here's another pattern I found which may be helpful for those trying to work around this ridiculous issue, without having to manually re-add artwork on all videos.

I had some videos from iPhone/iPad which were filmed in "Portrait Mode" and others in "Landscape Mode" (holding the camera upright versus sideways). This is the key differentiator that helped me fix it. The Media Kind "Movie" will only show thumbnails for the former while "Home Video" shows the latter! This is due to the native aspect ratio of the video, and the way Apple’s software interprets it.

Thus, in iTunes, right-click to do Get Info on all "Portrait Mode" videos and change Media Kind to "Movie". Then on all "Landscape Mode" videos, change Media Kind to "Home Video". If these are mismatched, looking in Videos on iOS you will see some thumbnails are missing and others are not. But if they are correctly sorted, all thumbnails show up!

One last observation - after making these changes and clicking “Sync” in iTunes, I found that some videos would just get the “spinning circle” and not play, as others in this thread mentioned. It seems the iOS device can get confused by changing the Media Kind. There are several ways to fix that. Un-sync the video from the device, then re-sync it – you need for it to show on Step 6 “preparing to copy items” and then see it actually re-copy over the videos in question. Alternatively, exit iTunes, fully close the Video app by double-touching the home button and sliding it up (or just reboot the device), then re-sync a second time – which usually helps it to detect the file changes.

I'm so glad you replied to this, because this was my problem after getting an iPad 4, versus my iPad 1. All of mine that didn't show up were all Home Video files (which iTunes categorized when I created the file and added to my iTunes library). So I selected all the video files, clicked on "get info" and changed them all from "Home Videos" to "Movies", then synced my iPad 4 and they all show up now. So glad I didn't have to change the resolution of the artwork file.

Same problems on ipad air.

Apple has changed or tightened up the requirements for media artwork.

Until someone figures out what dimensions makes itunes happy, live with it or as you said remove the artwork.

Try 242 px x 136 px .png. It is working! (ipad mini retina)

Try 242 px x 136 px .png. It is working! (ipad mini retina)

Or 270 px x 203 px (4:3) .png and .jpg are working too! (ipad mini retina)

I see it in the same way, too! Without announcement to change this thing really shows me that the focus is only on iTunes! I don't like to be pushed....

thanks for the advice...anybody an idea for portrait mode?

the videos from iTunes are showing in portrait mode, but i can't find out the size...

Amazing! The media type of my videos was home video and I changed it to movie ....so the other way around....and now I see the covers! Nothing changed in resolution...

Good job, your a legend. I hope they still change it back to the way it was though.

The aspect solution works. They need to be rectangular. Thanks for figuring this out. I had some that worked and some that didn't. It was very frustrating.

My problem is that I use a program for my tv shows that imports the metadata. So I can't resize the cover art. So do I change all tv series to home videos?