How to delete old device from basecamp?

I'm using basecamp 4.4.6. It shows two devices, my current unit and my previous unit, which I no longer have. Because of various problems I'm having using basecamp, I want to delete my previous unit from basecamp and everywhere else. I'm using Windows 8.1.

I found a previous forum post which said to remove a file named GarminDevice.XML. I can't find any file by that name. I can't find the path given in that forum post. (Yes, I told File Explorer to show all hidden items.)

I uninstalled basecamp and the garmin drivers. I deleted all files and folders with 'garmin' anywhere in the name. I deleted all files and folders with 'basecamp' anywhere in the name. I reinstalled the latest version of basecamp. Basecamp still shows 2 devices.

What do I do now?