Windows laptop works with Wi-Fi AP, phone claims it is connected but can't access Internet

Question

There's an Asus 240 MIMO Wifi access point. There's a laptop running Windows XP that uses that access point no problem for years so far. And there's an Android based HTC Desire S smartphone that has problems. The objective is to make the smartphone access the Internet via the Wifi access point.

I open "wireless networks" configuration pane, "enable" Wifi - it goes through "scanning" and "obtaining IP address" stages, says "connected to TheRightNetworkName". The Wifi symbol is displayed in the bar under the top of the screen. Yet when I try to open any page in a browser if wouldn't do so and claim there were problems accessing that page.

I tried the following (listed in this answer below, thanks to user Matthew Read):

• rebooted the phone - doesn't help
• checked MAC filtering on the AP - it is disabled
• disabled the firewall on the AP - doesn't help
• tried to change channels - doesn't help, the AP has 13 channels if that matters
• tried to change to 2.4 GHz - looks like it is already the only option, couldn't find any way to change the range
• didn't try to switch from WPA that is currently used to WEP because it feels quite scary - I can mess things up
• tried switching modes - b, g, b/g - doesn't help

How do I debug and resolve this issue?

Answer 1

Make sure that you are using DHCP on your phone; if you have a static DNS set and it's the wrong one, you won't be able to browse the web. Go to Settings->Wireless And Network->Wi-Fi settings, hit the context button (or right click button, or whatever you call it), select Advanced, and make sure Use Static IP is unchecked.

Answer 2

Assuming that the smartphone connects to the AP as you say, try the following.

• Take the IP of the phone.
• Connect to the same AP your laptop
• Run ping ip_of_phone from cmd (if you are using win) or from Terminal
• If you can do a ping means that something is wrong, perhaps with the DNS
• If you can not ping, probably something is wrong with IP assignment. Perhaps a two devices have the same IP. A common mistake is that people assign an IP to an AP and do not exlude that IP from the DHCP pool of the router.

Answer 3

First ensure the phone is using the right password for the network and try rebooting the phone.

Then play with with your AP, one of these at a time:

• Reboot it
• Ensure MAC filtering isn't on
• Try disabling any firewall it might have
• Ensure it uses channel 1 or 6 or 11 (assuming you're in an 11-channel region)
• Try switching to 2.4 GHz if it's broadcasting on the 5.0 GHz band
• Try switching from WPA to WEP encryption or vice-versa
• Try switching to or from mixed mode (e.g. 802.11 b/g rather than just 802.11b, etc.)

If nothing changes, please provide your phone model and I'll try to help further.