When you start a game with Online-Fix installed for the first time, it might detect a .dll file as a virus, which is not true.
1
Start the game
Start the game which has Online-Fix installed, and wait for the Windows Defender pop-up to appear.
If the pop-up doesn’t appear, open Windows Security from the Start menu, open Virus & threat protection, then Protection history and select the top item.
2
Click on the Windows Defender pop-up
When the app opens, it will ask for administrator permissions.
3
Dismiss the false positive
Click on Actions > Allow on device. It will ask for administrator permissions again.
4
Restart the game
Just to make sure everything will work.
5
Congrats!
If you’ve followed all of the steps correctly, you should now have prevented Windows Defender from removing the detected file.