If you don't need this driver (for operating an external Western Digital USB-drive), you may delete it:
Right-click on Start, then click Windows Powershell (Administrator). In the PowerShell window, enter and run the following command:
pnputil /delete-driver oem**##**.inf
Replace ## with the number that appears on the appropriate line of the Windows security message.
You should now be able to activate the memory integrity option.