If running as an administrator and the repair option are not working, and your firewall and antivirus are not blocking the game, please try the following:
Open the game installation directory “Zenimax Online”
Open the folder named “Launcher”
Inside the “Launcher” folder, there is a folder named “ProgramData”
Open the game installation directory “Zenimax Online”
Open the folder named “Launcher”
Inside the “Launcher” folder, there is a folder named “ProgramData”
Delete the “ProgramData” folder
Open the launcher and download update
Click “Play”
If this doesn't work then go to the folder again and delete ProgramData folder again, then Run Launcher as Administrator, it makes a lot of difference. Trust me.