Oracle Virtual box extensions install fails with VERR_ACCESS_DENIED due to McAfee

Installing Virtual Box 5.1.2 extensions on windows 10 failed with this error:

VBoxExtPackHelperApp.exe: error: Failed to rename the temporary directory to the final one: VERR_ACCESS_DENIED ('D:\Program Files\Oracle\VirtualBox\ExtensionPacks\Oracle_VM_VirtualBox_Extension_Pack-_-inst-4288' -> 'D:\Program Files\Oracle\VirtualBox\ExtensionPacks\Oracle_VM_VirtualBox_Extension_Pack')

After seeing several people on the net pointing to the antivirus, I disabled the McAfee real time virus scanning that came for 1 year with my Dell PC:

1. Right click System Tray McAffee LiveSafeIcon
2. Change Settings > Real Time Scanning
3. Turn off
1. Leave In 15 minutes

Then I reran the extensions installer and all went well.