Internet connection lost on 1 PC

[octafish]

There are 3 PCs on my home network:

1/. Vista Ultimate 32 bit Intel Dual Core desktop - Ethernet connection
2/. XP Home laptop Intel Celeron laptop - devolo AV200 mains networked
3/. XP Home Athlon XP1900 desktop - Ethernet connection via USB to Ethernet adapter.

They run through a KCORP 108 G wireless router. Company now defunct but router ostensibly OK.

Pure Networks 'Network Magic' used.

Problem: Up until yesterday all 3 PCs connected to the internet and to the local network. This is a very long-standing and (so far) extremely stable set-up.

Since yesterday PC #3 has lost its internet connection whilst maintaining its local connection.

I've tried rebooting the router, disabling security options on the router, swapping over LAN connections on the router, swapping the LAN connection on PC #3 for a devolo link. Unfortunately the problem persists.

Has anyone got any ideas on what could be causing this? I can access all 3 PCs from each other!

Thanks in advance.

Steve

 

[rf6647]

Check the firewall settings. I wish I could recall the specific problem with Zone Alarm that caused periodic disconnects from the internet. Flushing DNS temporarily restored the connection. Using the correct setting overcame the problem. I wish I could offer specifics.

 

[octafish]

Thanks for replying rf6647.

It turned out that an important MS IP security patch caused thousands who use ZoneAlarm to lose their internet connection.

Solvable by updating with the new ZA versions made public yesterday.

I'm attaching a pdf of ZA's page on this, for information.

Thanks again.

Steve