I was using LogMeIn and I disconnected one of my monitors when we moved to a new office. Just haven’t hooked it up yet. I also installed the new NVIDIA drivers, so haven’t figured out the root cause of the DPMS error yet.
Anyway, I couldn’t blank my screen when I logged in and the LogMeIn DPMS driver installation failed every time.
It turns out the fix was pretty simple. LogMeIn by the way is no help, which is why I am posting this here.
Right click My Computer -> Manage.
Go to Device Manager.
Go to Monitors.
Uninstall each monitor. Right click, hit uninstall.
After you removed EVERY monitor.
Click the computer name at top, Right click and hit Scan for Changes.
Now. Log out and back in. Honestly, you can hit the Blank Screen toolbar button in LogMeIn and it "should" prompt to install the DPMS drivers. If not, log out and remote back in.