I'd still like an answer, but I worked around the problem by installing the Trial version of the product from another location on the Adobe site. This approach doesn't use Adobe Application Manager at all, rather uses Installation Assistant.
After downloading, when running set-up.exe, I was given the opportunity to select "I have a subscription" and with my adobe ID was able to install the licensed version.
Sure like to know why the aam: protocol is not recognized. When I look at installed Plugins in my FireFox, it clearly shows AdobeAAMDetect 18.104.22.168.
Next time I try to install CC software, I'll first try disabling and/or uninstalling this plug in and see if a newer version of AAM detect gets installed, as well as the AAM itself.
have you tried updating the Adobe Application Manager ?? seems like its not getting detected on any of the browsers for you . here's the link from where you could try downloading the same .