Hi Peter,
I think I may have found the cause. It appears that Malwarebytes that I use on my PCs is the problem. If I enter the IP address in the MB exceptions (not the URL as first requested), then Playback runs OK. I can't say that there is no problem with the site, but I have found MB to be over protective with other sites ( I.e. the Matronics Forum).
This started as I wanted to compare Playback to Flysto.net Early indications are that Playback appears to shows more traffic, as flysto only appears to show ADSB traffic. So far, I have been using the kml files from Skydemon, but I would like to use the PAW trk files.
It's been interesting trying to find a way to convert the PAW trk files into kml, as required by flysto. I'm trying to use the technique suggested by Richard Hine in this thread
http://forum.pilotaware.com/index.php/topic,1574.msg17338.html#msg17338but as I'm not familiar with Perl, I'm finding it challenging at the moment
Cheers BobD