First install AutoHotKey. Now create a script that looks like this :
Save it as a .ahk file and double-click the file to run it. Now you should have inverted the mouse wheel scrolling.
All information from here, though it has been modified with the addition of the $ prefix to prevent the Send commands from being captured again by the script (which exacerbates the MaxHotkeysPerInterval issue)
Add the following to the script to invert horizontal wheel scrolling:
Scrolling with the wheel might exceed the default limit of hotkey presses in a specified time interval. By default, this is 70 hotkey presses (#MaxHotkeysPerInterval) per 2000 milliseconds (#HotkeyInterval). Add this directive to your script to increase the limit from 70 to 200 hotkey presses per interval: