Windows 11 game downloaded from the Xbox app disappeared after the SSD was disconnected and...

Could be then that the data has gone missing because of the overheating trouble you had, the gane files should be located on the "windowsapps" folder that is located on the root of your device, you can manually delete those files and reinstall the game,.or even try to reinstall the gane before deleting the files

You can also try this as sometimes helps the Xbox app to update the information about games installed

Complete given below directions to reset the app in Windows

Step 1: Open the Settings app. This can be done by clicking its icon in the Start menu or simultaneously pressing Windows logo + I.

Step 2: Click the Apps category icon and then click Apps & features to see all installed apps as well as classic desktop programs.

Step 3: Click on the app that you want to reset to see the Advanced options link. Click on the same (advanced options link).

Step 4: Finally, click the small Reset button. When you click the Reset button, you will find a small dialog box with “This will permanently delete the app’s data on this device, including your preferences and sign-in details.” Click the Reset button in the opened dialog box to reset the app.

Step 5: Once the Reset is done, you will see a check sign next to the Reset button. And restart the Pc

I saw that you marked as not resolved, could you elaborate on why please?

Hi HAN! My name is Ricardo an independent advisor ready to help you with this situation!

I understand that the device was unplugged from the PC, when you plug it back, was after you plugged another device, as it's possible that the drive letter was changed after you plugged it back, if that's the case, have you tried to change the letter back trough the disk partition tool?

Could you share a screenshot of the error message that you see when you try to launch the game?

Well, it isn't here either...... I have tried everything I know but still cannot find a possible way.

The reset needs to be done with the Xbox app not the game, but if it doesn't appear among your installed games you as I mentioned can delete the files trough the "windowsapp" folder and disable optimization delivery