In "Devices & Printers" the mouse shows up with the correct name and even picture. This leads me to believe the correct drivers are in fact installed.
The horizontal scroll by mousewheel does in fact work perfectly fine in Word, which further leads me to believe that this problem is in Excel, not in the driver.
I tried a few others as well:
Word: works
Excel: doesn't work
PowerPoint: doesn't work
Outlook: works
Visio: works
Visual Studio 2012: works (not in all panes, tho)
Explorer: doesn't work
Internet Explorer: works
Firefox: works
Photoshop CS5: doesn't work
Command prompt: works (genuinely surprised :P)
Notepad: works
Paint: doesn't work
The fact that it works in so many applications and doesn't work in some other, indicates that it is something that has to be implemented by a developer of that application, and it isn't something that "magically" works like vertical scrolling usually does.
For now, as far as Office 2013 is concerned, this problem exists only in Excel and PowerPoint (although getting PowerPoint to show a horizontal scrollbar is a challenge in itself). If this problem can be fixed in the Explorer as well, that would be awesome.
This is the same situation that I face - exactly.
Does not work in Excel or Powerpoint, works in Word though. Operating windows 7 64b and Office 2013, also had this problem in Office 2010.
Using Logitech G700S with Logitech Gaming Software v 8.52.15 - all drivers up to date as @ 4/4/2014
Not an isolated incident, have had this issue with many different mice. (Also Logitech Performance MX x multiple mice)
Somehow a few months ago on Office 2010 it started working for no apparent reason, now on a new machine and new job I've got the same problem