Is Norton blocking inbound Skype calls?

Hi

 

I'm having a problem with Skype and wondering whether it might be something to do with Norton Internet Security.

 

I have a Skype phone number and in Privacy settings have clicked "allow anyone to contact me" and saved this setting. However it never seems to stay like this for long and when people try to call the number it rings once and then goes to an engaged tone. When I go back to check privacy settings it will have changed to "only allow people in my contact list to contact me".

 

Have spoken to Skype about this and they think it may be to do with firewalls, etc.

 

Is this something anyone has come across before? Any ideas how I can solve it?

 

Thanks

medic1