I'm using TeamViewer on a Windows computer to control a iMac. The keyboard on my side is this, but I got that it works like this one (when I push \ I obtain `, when I push Shift-\ I get ~, and so on). At the beginning I thought it was unavoidable, so I started to get used to this changes (hard to do, since I write in latex and \ is the most important non alphabetical character); accidentally I changed the settings such that the keyboard is mapped in the right way, but I don't know how. So far, it's fine; then I unfortunately (and accidentally) turned things back, so I think it's the moment to understand how to menage this settings.

In system preferences>keyboard I see there's only the italian keyboard. Furthermore, even if I add and select other keyboards, I always get ~ when I press Shift and \ (the originary behavior).

Could the problem concern the remote control??