Google is your friend.
So here's the fix.
Step 1: Uninstall the drivers. No frills here, the add/remove programs in the control panel will suffice. Go on, click the button.
Step 2: Do NOT let it reboot at the end. You'll do that in a minute.
Step 3: Open Explorer. Navigate to %SystemRoot%\system32\drivers.
(For most of you this will be C:\Windows\system32\drivers)
Step 4: Here's the payoff. If you have the problem this fix solves, you will find in this directory a file named "wdf01000.sys". It doesn't matter what version. Don't bother with the properties. Rename the thing. It doesn't matter what you rename it to as long as the file isn't accessible as "wdf01000.sys" anymore. You can probably even delete it, but I personally renamed it "wdf01000.sys.crap".
Step 5: Reboot
Step 6: Install setpoint drivers.
After easily 20 hours worth of cussing, threatening, searching, and trial-and-error, it came down to the installer failing to properly install all of its required hooks when that file already exists. If the file does NOT exist it gets installed by setpoint - and then the blasted thing works JUST FINE.
Step 7: Use mouse.
http://forums.logitech.com/logitech/boa ... e.id=12046