fallout 76 won't launch

Toby hi there I have been having the same issue and while I have not fully fixed it, I have had success in launching and playing the game, what I had to do was create a new account, I did give it admin rights just to be safe, opened steam launched the game and it worked perfectly, it is not an issue with the game in particular but I believe it is an issue between windows permissions on the game, now that I am able to access it I am going to try and cross reference settings between the two accounts and hopefully I will come to a solution

I'm on windows 10 and i just checked it's all games

I've tried all 3 and it still won't launch

Thanks for the extra information Toby

Please try this:
A.
Press Windows button and type Services

On Services App from the list of results, press right-click and run it as administrator

Scroll to the bottom and find the following services:

IP Helper
Xbox Live Auth Manager
Xbox Live Game Save
Xbox Live Networking Service
Gaming Services

And do this with each of the services listed above:

Right-click over the service and select Properties.
Find the Startup type section and make sure it’s set to Automatic (if not, change it to automatic)
If the service isn’t started, click Start to start the services

Restart your PC and try again

B. Can be a bit odd but:
Open the Control Panel in Windows.
After opening the control panel, set the “View by” on the top-right corner to “Large icons“.
Click on the “Network and Sharing Center” option.
Here, click on the “Change adapter settings” link on the left panel.
Now, right-click on the active network adapter and select “Properties“.
Go to the “Networking” tab.
Here, uncheck the “Internet Protocol Version 6 (TCP/IPv6)” option.
Click on the “Ok” button to save changes.
Then close all the windows, restart your PC and try again

C. Reinstall Gaming Services using powershell command

Press Windows key + X and then select Windows PowerShell (Admin).

Type or copy / past the following command and press Enter:

Get-AppxPackage *gamingservices* -allusers | remove-appxpackage -allusers

Restart the PC and Open the Xbox application.

A blue notification with the following message is going to appear at the bottom:
"This app needs an extra component. Gaming Services is needed for playing some games. Administrator approval required. Install"

Select Install to reinstall Gaming Services, once installed check again

Hi and thanks for reaching Microsoft Xbox gamer's community. My name is Josef.
I'm an Independent Advisor and a Microsoft Xbox user like you.

Hope you're doing great today despite this TOBYYOST

Additional information is needed, please tell me:

Are you using windows 10 or 11?
Is this happening only with Fallout or if you try a different game something similar happens?
When you say repairing and restoring, do you mean the game itself or the game and other apps?

And besides that, did you tried something else?
In that way I can advise you different things or how to proceed.

———
In the meantime please double check if everything in your PC is up to date

Open Settings, click Update and Security and then Windows Update
Click Check for Updates

Click the Download and Install Now option, if available (Install optional updates as well)

Now, check the Microsoft Store for any updates on the Xbox apps and its services and update everything too. (Click on get updates)