UPDATE July 31, 2015

A good solution for users who have upgraded from Windows 8 / 8.1 is suggested in the comments by Tobias Shen:

The final solution was I uninstalled my Lenovo Pointing Device driver [device manager, mouse and other pointing devices], went to their website and downloaded the Windows 10 mouse driver.

After a reboot, just start checking for updates from Windows Update to start the download and installation of the updated driver.

UPDATE: With the latest builds of Windows 10 you can install the updated Synaptics drivers through Windows Update , which no longer requires this procedure.

I’m testing the Windows 10 Technical preview: i find some problems, but the new microsoft’s OS is light and stable.

However, on my Lenovo notebook with Synaptics touchpad the “two-finger scroll” (osx-like, very useful) seems not work.

After a quick search on support forums, i have found a very simple solution:

  1. Open Registry Editor (Windows + R, type regedit and hit Enter)
  2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Synaptics\SynTPEn
  3. Create a new DWORD called UseScrollCursor with a value of 0.
  4. Logoff or Restart

That’s all!