Firstly, if you're using Chrome there's a known issue with the latest version on Windows - see here for a workaround: http://forums.adobe.com/message/5201084
Assuming that your problem is with all content, there are a couple of things I can think of. Firstly, Flash Player recently changed the location it looks for the .telemetry.cfg file. Rather than under
%HOMEDRIVE%%HOMEPATH%, it now looks under the
%USERPROFILE%environment variable. On the vast majority of machines these point to the same place, but it's possible that they don't on yours. If not, to use Scout you'll have to either change them to point to the same location, or manually copy the .telemetry.cfg file across. The next version of Scout will write to the correct location.
If this isn't the problem, the only other thing I can think of is your firewall settings. If you're able to connect to Scout, then the only thing remaining is that Flash Player is being blocked from opening a connection. Try disabling your firewall, and see if this works.
Aha! The location of the .telemetry.cfg was indeed the problem. Once I copied it over to the %USERPROFILE% it worked perfectly.
I'm assuming this has something to do with my windows user account being connected to a corporate domain.
Thank you very much for your help.