Firewall alerts - should I worry?

[MJDale]

I run Zonealarm on my PC which generates a fair amount of alerts. I have checked out where these alerts are coming from. Some are from my ISP - is this normal? and why? Some are from companies I have never heard of - I even had one the other day from BT - why is this? Should I be contacting these companies and asking them why they are doing this? If so can someone suggest appropriate wording so it sounds a bit more like I know what I am talking about!

[howardpiercy]

There are 2 good websites that might help you with your firewall problems. The first is http://www.zdnet.com/eweek/filters/resources/0,102
27,6016830,00.html it is a great site and has lots of info you cant find anywhere else on getting help with your firewall, learning all about firewalls and it even has forums and news groups where you can discuss how to get rid of any firewall alerts. Also check out http://www.interhack.net/pubs/fqfaq/ - it lists common questions and problems with certain software and how to get around them.