Firewall setting and inability to renew IP address?

[Jeff]

I have a 3-pc home wireless LAN, WPA protected, that connects to the
internet through a router and cable modem. All are XP Home systems.

Has been working with no problem for almost a year and now, "suddenly",
although the wlan has no problem (can connect and see all PCs fine), on one
laptop, the ip cannot renew itself properly. This demonstrates itself in
that when the laptop goes into hibernation and then restores itself, very
often it loses its internet connection (LAN remains on) and refresh usually
does not work requiring a reboot.

In searching for a possible cause I am now focusing on my Zone Alarm
firewall as the possible cause because a fresh installation of Zone Alarm
seems to have occurred during a recent ZA update. So I had to reset again
all the program permissions in ZA.

Looking into the ZA settings, I notice:
- the wireless adapter is in the internet Zone, but in the "advanced
settings" there is are 2 options that are not selected (the default) and I
wonder if they might be the problem. Before setting them to selected, I am
asking for help in case these are dangerous to select. They are
a. "Allow Outgoing DNS/DHCP in Trusted Zone on High setting"
b. "Allow Outgoing DNS/DHCP in Internet Zone on High setting"

Could these be the problem and should I select one or the other? Would that
be safe?

Jeff

 

[Steven L Umbach]

You can allow both of those settings. DHCP is needed to obtain/renew IP
address when an operating system is configured to obtain IP configuration
automatically from DHCP server and DNS is needed to resolve internet host
names. You can use the command ipconfig /all to see the current tcp/ip info
and compare to computers that are not having the problem. If the operating
system can not obtain an IP address from the DHCP server it will assign
itself an IP address via APIPA and you will see the IP address start with
169.254.x.x .

Steve