Reinstalling Xbox One game from disk, when I installed it on external drive, and have "misplaced" that drive?

Question

Yesterday I brought my Xbox One to a friend intending to show him the platform, the games, the graphics, features, etc.

However, I had forgot to bring the external drive. In my haste when unplugging everything at home, the disk was left behind.

Unfortunately I had installed all my games on that disk.

However, I had brought the Battlefield 4 disk, as it was already inserted into the console before I took it with me.

However, reinstalling from the disk didn't seem to be an option, nor to uninstall it. The only option I had was to install it from the store, which started a 45GB download which took all night.

In the above scenario, is it possible, and I just didn't find out how, to do the following:

1. Uninstall the game, or make the Xbox forget that it was installed on the external disk, preparing for a new disk-install?
2. Reinstall from the disk, and not only from the store/download?

For instance, what if the disk was lost, or destroyed, or otherwise permanently gone, what would I do then, would my disks be worthless?

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OK, since it seems nobody else has experienced this or not quite being able to understand what I'm seeing, I did this:

1. Turned off the Xbox One
2. Unplugged the external drive
3. Turned on the Xbox One

As before, the Battlefield 4 disk is in the console.

On the home screen I can see the disc tile lower right, showing Battlefield 4. If I use the controller to activate it, the BF4 screen goes fullscreen briefly, and then returns to the home screen with a gray error message that says the following (verbatim):

For {0}, connect your external storage
If you have the storage device or the disc, use that. Otherwise, install Battlefield 4 from the Xbox Store. (0x87e000c8)
[See in Xbox Store] [Cancel]

If I activate "See in Xbox Store", it goes to the store item for BF4, where I can Install/Pin to Home/Rate. Activating Install installs the game, but from the online store. This takes a lot of time.

If I return to the home screen, navigate to the disc tile (again) and hit the menu button on the controller, I have these choices:

• Go to full screen
• Pin to Home
• View game details
• Manage game

If I use "View game details", again I end up in the store. If I use "Manage game", I get to a gray screen, with the BF4 icon on it, and an option on top of the big icon to install it. Activating that informs it it'll take a while. When accepting that, it is queued up, 35.3GB. None of this spins up the disk, and it is a slow install, so it is being installed over the internet.

OK, so that didn't work, let's see what I see under storage management.

-- and now I found the solution, I will add my own answer here.

Answer 1

While writing out a more detailed description of the behavior, I stumbled upon the solution myself.

When you try to install the game over the internet, just let it start, and then cancel it. This will both remove the installation and download from the queue, but apparently also remove the knowledge of the installation from the Xbox One.

So:

1. Start the online install
2. Cancel it
3. Return to the home screen
4. Notice that the disc tile has now changed to "Install disc"
5. Activate the disc tile to start the installation from the disc.

This worked, the game now installs from the disc. Obviously any downloaded DLC's will still need to be downloaded, but for the purpose of this question this is not relevant.

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Now, what do you do when you get back home and want to plug in the external drive?

Here's what I did. I first uninstalled the game using the storage management.

This makes my Xbox One forget that I had the game installed. Make sure you don't delete any savegames you have on the console.

Then, you turn off the Xbox One, plug in the external drive, and turn it back on.

Once you do that, the disc tile still says "Install disc". Ignore that. Instead either use your pinned link to the game, the tile for the game (if it shows up on the home screen), or navigate to your games and apps list and activate it. You should get a message saying not to unplug the external drive, and that your game will be ready soon.

A few seconds later you can try again and the game should now start.