No reaction on TV12 - Mac

I have been using TeamViewer 12 on my iMac for some while now. My OSX is 10.12.5

Recently I have run into a strange problem. My interface in Teamviewer doesnt respond to any clicks, if i click the Windows Machine "A" i usually connect to, it just does.. nothing. The status bar in the bottom of the program doesnt change and theres no reaction from TV12 at all. 

When I do the same from my other Windows Machine "B", I can connect to to Windows Machine "A" with no problem. I have checked the different versions of TM - and they all seem to work just fine. But on Mac, something is wrong. I cannot connect to Windows Machine "B" from my iMac aswell.

I tried verifying this on my Macbook Air - and the same kinda happends. I can connect to Windows Machine "B" and "A" but not the iMac. So, it goes to reason, that something must be up with iMac TV12. I removed it, and reinstalled it - logged out and in - its the same problem.

Now, of all my TeamView installations, I do believe my iMac install is the oldest. So it goes to reason there "might be something" with maybe certificates or.. well - something, that has been kept through all the versions. 

Any hint would be appreciated.