Bump...
I have a Samsung Galaxy Tab S 8.4 and my memory was really full (couldn't update apps anymore). So I decided to buy a micro sd card for my tablet.
When I plugged it in, I started moving my biggest games (in size) and also my Facebook app, but stopped when I noticed their icons turned into green android icons. I thought it would fix itself if I restarted my tablet, but it only got worse.
The green android icons are now grey android icons and when I try to start the app it says that "app isn't installed". If I try moving it back to the device storage it says "app doesn't exist".
I really hope I can get the apps back, there was some serious progress in those games.

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