I upgraded from 2.1.9 to 2.1.10 and now all of my connections require I click the yes box on the warning to connect.
Prior to this version there a check box to not ask again for this computer.

Is there a new option for this?

That is very odd because 2.1.9 and 2.1.10 share the same RDP 6.1 code. Check to make sure that you haven't had a ceritificate expire recently. That will remove the checkbox in my tests. The security checkbox is okay with a root authority not being known, but it is NOT okay with a certificate that is out of date. Keep me updated on this. Note that the warning dialog is thrown by the Microsoft RDP control and is not something I can generally "code around."

I uninstalled and reinstalled 2.1.9 and the box can be checked. Also it doesn't come up on ones I had checked before that were coming up in 2.1.10. I just re-installed 2.1.10 and and getting the same results as earlier.

I have an idea of what it might be. It might be when I set the username caching feature (so-called "public mode") to on. That may also affect the checkbox with invalid SSL certificates. I'll look over it next week. If that is the culprit, I will probably add an option to turn public mode on or off. I set to "on" because I felt the so-called "private" mode could pose a security "information disclosure" problem in some situations by having the remote desktop cache usernames, but it's possible that some people are willing to live with that for other features like the one you describe.

Am I the only one complaining about this?
I just tried updating to 2.1.12 and am having the same issue.

Did you go into the options and turn public mode off? (check the box that says "Cache connection properties" under General).

Thanks that worked, I missed that option.#-o