Install Size Missing from Xbox Store details

The game install sizes are also listed on the Xbox One game store, on the console and here on Xbox.com. The download sizes are exactly the same as the disc install sizes.

As to the install size to actual game size ratio, that one is easy to explain. The size of a game install isn't necessarily bigger because the game is 'bigger'. The size really depends on the game assets, things such as textures, high definition audio and
HD video sequences. This explains why AC4 is 7.63GB on Xbox 360, and 20.81GB on Xbox One.

Further to this, the 3.7gb update has installed, I've gotten in to the settings for the preview program and disconnected my xbox from it and I now have a 3.6gb update to install. Any explanations?

The console OS is around 3.7 GB depending on the region. When you left the preview program, that update would have rolled you back to the latest public update.

If you miss an Xbox update the file size is around 3.7 as it needs to install the OS again if you do not miss an update the file size is around 500mb. (by miss I mean where you don't update your console and a new update comes out).

Check Xbox Store and look on your missing games, if you can install it from Xbox Store, do it, if no something is wrong, subsription/sharing account etc.

I've been having troubles with Wasteland 3 from the xbox-gaming-pass two times already (the latter one just solved right now). The game from one day to the other started crashing at startup displaying a message regarding an error due to an update that has to be installed (but updating was grayed out in the xbox-app, and microsoft store did not see the game at all). What works for me is searching the game in the Microsoft Store and then not clicking the game-pass version, but rather the one from the store itself. It then starts downloading the update (actually it says that it's 'installing the game' above the progress bar, but the download size of ~3GB vs >20GB of the initial install through the xbox-app seems more like this missing 'update' to me). I hope this works for other games too, at least it's a trigger for Wasteland 3 on xbox/game-pass.

Its installing! I had to uninstal via games and apps, then had to reinstall from the store ... so basically uninstal then go forza 3 via the store, then go to mmanage, then install all.. the size is 47.3 gb for standard edition