• I've (re)installed the latest AppleWirelessMouse64.exe from the Bootcamp support software (tried both 5.1.5722 and 5.1.569) and also the BlueTooth driver.
• I've tried switching the mouse off and on again (disconnecting, reconnecting), rebooting, unpairing and (re)pairing
• I've tried MagicUtilities; at first it installed but then my mouse became near unusable. The pointer would jump instead of move with second+ intervals, the mousebutton(s) didn't react to anything. Even not after rebooting, again trying all of the above with pairing, unpairing, switching off and on etc. On boot the mouse worked fine; I could click and move it without issue until MagicUtilities loaded (in the taskbar). Then it seemed to break. So I then uninstalled the software. However the mouse still kept "jumping". It turns out MagicUtilities als installs a driver but doesn't uninstall it (WTF) when you remove their software. Uninstalled the driver, which failed for some reason on several occasions, but, a couple of reboots and "persuading" later I had my mouse (or mice) finally back to where I got started.

Since I've exhausted all of my ideas (I also tried looking at the registry to find differences etc. (didn't change anything ofcourse)) I tried to go back to giving MagicUtilities another, very, very reluctant, shot; however: it won't install anymore: "The required Magic Mouse Driver installation failed. Error code is -2147418112". Again, I've tried rebooting etc. but that doesn't help anything.

• I've (re)installed the latest AppleWirelessMouse64.exe from the Bootcamp support software (tried both 5.1.5722 and 5.1.569) and also the BlueTooth driver.
• I've tried switching the mouse off and on again (disconnecting, reconnecting), rebooting, unpairing and (re)pairing
• I've tried MagicUtilities; at first it installed but then my mouse became near unusable. The pointer would jump instead of move with second+ intervals, the mousebutton(s) didn't react to anything. Even not after rebooting, again trying all of the above with pairing, unpairing, switching off and on etc. On boot the mouse worked fine; I could click and move it without issue until MagicUtilities loaded (in the taskbar). Then it seemed to break. So I then uninstalled the software. However the mouse still kept "jumping". It turns out MagicUtilities also installs a driver but doesn't uninstall it didn't remove it in my situation. Uninstalled the driver manually, which failed for some reason on several occasions, but, a couple of reboots and "persuading" later I had my mouse (or mice) finally back to where I got started.

Since I've exhausted all of my ideas (I also tried looking at the registry to find differences etc. (didn't change anything ofcourse)) I tried to go back to giving MagicUtilities another, rather reluctantantly, shot; however: it won't install anymore: "The required Magic Mouse Driver installation failed. Error code is -2147418112". Again, I've tried rebooting etc. but that doesn't help anything.

• Connecting the MM2 to my MacBook air. Scrolling works fine. Ofcourse.
• Since my MM1 has a name like "<joe's mouse>" I even tried renaming the MM2 to "<joe's mouse>" on the MacBook and then going back to my PC, connecting the MM2 (solely) and hoping it would pick up the MM1's settings. To no avail, as expected. But there's always that little spark of hope...

• Connecting the MM2 to my MacBook air. Scrolling works fine. Ofcourse.
• Since my MM1 has a name like "<joe's mouse>" I even tried renaming the MM2 to "<joe's mouse>" on the MacBook and then going back to my PC, connecting the MM2 (solely) and hoping it would pick up the MM1's settings. To no avail, as expected. But there's always that little spark of hope...
• Disabling Bluetooth Battery Monitor, thinking it may interfere somehow. Didn't make any difference. It does, however, report two mice and two battery levels which is nice.