Hello, I managed to download UltraChannel when it was free and I've been using it without issue until now. When I got the free download a couple years ago, I didn't have to make an account here. I've made an account just now for this very issue.
I have the same activation error as the OP. My issue may be different because I was forced to do a factory restore on my laptop (Windows 8.1 64bit, Toshiba Satellite). In my quest to find a solution, I was brought to this thread and I followed the directions given here by deactivating my plugin etc. Now UltraChannel isn't showing at all in my activated licenses so there is no way I can activate it at this point. By the way, I don't use an iLok, just my ilok account. I'll be happy to give anymore necessary info to solve this problem. Thanks for any assistance.
If you click on "Available" at the top of iLok License Manager, does the UltraChannel license show up there? If not, can you send an email to firstname.lastname@example.org with your iLok account name? Sometimes these issues happen when you do a factory restore of your computer, and we have to deposit a new license.