Hey there,
Limitations of Blizzard Support for Activision Titles
We only handle the distribution of the game client for Activision. We will assist with anything related to the desktop application and anything with the game client that involves purchasing, activating, downloading/installing and launching. Anything that occurs after you can press the play button is going to be addressed the Activision support portal: Support Options | Activision Support
As for the error you are seeing, This error indicates either data corruption in a way that the repair tool cannot fix, software conflicts, permission issues or network issues preventing access to the data the app needs for updates/repairs. The following steps should solve that issue though keep in mind it is intended to correct issues with the Blizzard App itself not the game client.
Try doing an extended power cycle on your system. Turn off all devices including the modem. Wait 30 minutes, turn on the modem, wait 5 minutes, turn on any network devices, wait 2 minutes, turn on your computer and try the game.
You can try switching your DNS settings to use a free public DNS servers instead of your ISPs Servers:
We do not have individual steps for specific modems or routers so if you need assistance accessing or updating the devices, contact the device maker/provider.
From here we need to manually clear the Battlenet Desktop Application and all supporting data from the system. This will not remove existing game clients.
- Open file explorer/file manager (Right Click Windows Start)
- Navigate to the folder where the desktop application would normally be installed. Delete that folder if it exists (usually program files x86)
- Type the following into the address bar (not the search bar): %APPDATA% and press enter.
- Delete the Bnet and blizzard folders inside the appdata folder if they exist.
- Repeat steps 3 and 4 with %PROGRAMDATA% %LOCALAPPDATA% and %TEMP%
- Empty the recycle bin.
- Now reinstall the app to the C: Drive.
While I typically save this step as a sort of last resort due to the size of the game client, it does often solve issues like this where other steps sometimes fail.
- Click Options (gear symbol next to the install/update/play button)
- Click Show in Explorer. (leave this window open while you perform step three.)
- Go back to Options and select Uninstall and go through the process to remove the core files and association to the desktop application. (Skip to step for if unable to perform this uninstall)
- Check the opened file explorer window to see if the game folder was deleted when the game was uninstalled. If it was not, delete the folder manually.
- Go back to the Blizzard App and reinstall the game client through the Blizzard App.
Note: Do not install the game client to an invalid directory. This includes the Battle.net Desktop Application’s own folder or any subfolder, Downloads, Desktop, Windows Temp. This also excludes any external, network or cloud based storage.
This should help solve the issue for you and get you back in and playing. Please note if you encounter any other issues once you can press the blue play button you will need to reach out to Activision through the portal I linked earlier.