After browsing around on the internet I found a Microsoft Knowledge Base article about an advise to block the use of RSA certificates that have keys that are less than 1024 bits long… : http://support.microsoft.com/kb/2661254

To skip all the text on this page to the command one needs to unblock this restriction and for example set the minimum key length to 512; run the following in a elevated command line (cmd.exe ‘run-as-administrator’):

certutil -setreg chain\minRSAPubKeyBitLength 512

Now the “Continue to this website (not recommended).” is back!