This error indicates that you do not have permission to install the game. Try the steps listed below to resolve this. These steps are written for Windows 10, so some locations may vary slightly on other versions of Windows.
Disable background applications
Background applications can interfere with the Epic Games Launcher so disabling these may resolve your issue. For instructions on how to do this you can visit this article here.
Confirm you’re an administrator on your computer
- Click on Start.
- Type User Accounts and press Enter.
- If you are an Administrator, Administrator will be listed underneath your username.
Run the Epic Games Launcher as an Administrator
This will ensure that you're able to install games to protected folders on your computer.
- Right-click on your Epic Games Launcher shortcut.
- Click on Run as administrator.
Confirm you have read/write access to the folder
- Navigate to your selected install location.
- Right-click and select Properties.
- Select the Security tab.
- Select your username in the Group or user names box.
- Verify that there is a check under Allow beside both Read and Write in the Permissions box.