High Sierra update 10.13.4 and 5 fail to install on my Mac Pro (Mid 2010) running 10.13.3. What should I do?

High Sierra update 10.13.4 and 5 fail to install on my Mac Pro (Mid 2010) running 10.13.3. What to do next?

I have tried performing the updates via the App Store notifications and they always result in a failure to update. I have downloaded the update packages and tried to install that way and they fail as well.

The package opens, reboots, the screen comes up "installing update" then when the progress bar is about 1/8th of the way across, the machine reboots and after startup displays the notice that the update failed to install.

I am NOT using any Anti Virus Programs,

Thanx!