WRT160N - Router - wireless laptop unable to PING other devices

Question

One of the laptops connected wirelessly on my WRT160n is uanble to PING or be PINGed by any other device on my network.  Could this somehow be due to the router settings(firewall perhaps?) and not the laptop itself?
1) The laptop is able to PING and be PINGed when connected to another wireless router at another location. 
2) Other wireless laptops on my WRT160n network are able to PING and be PINGed by other devices. 
As a result, I am not able to print or share files on this network.
Any idea where I should start to isolate what may be causing this.
Thanks!

Answer 1

The router's firewall does not cause this type of problem.  As long as all computers on the network can access the Internet, then the router does not put up a barrier to file and printer sharing, or pinging.  The only exception to this rule is if "AP isolation" is set to "enabled" in the router  ---  then in this case, wireless computers can only access the Internet.  By default, AP isolation is disabled, and you should leave it disabled if you want to share files and printers with your wireless computers.
The most common cause for the problem you described is a computer software firewall problem.  Go into the computer software firewall on each computer in your network, and set it to "trust" the other computers on your network.  Also, verify that you do not have two computer software firewalls (such as Windows Firewall plus another computer software firewall) running simultaneously on the same computer.  If you do, turn one of the computer software firewalls off.  On any given computer, never run more than one computer software firewall at the same time.
The next most common cause for the problem you described is simply a poor wireless connection.  Note that poor wireless connections can occur even if your computer shows "5 bars".
There are many causes for poor wireless connections, and many solutions:
First of all, give your network a unique SSID. Do not use "linksys". If you are using "linksys" you may be trying to connect to your neighbor's router. Also set "SSID Broadcast" to "enabled". This will help your computer find and lock on to your router's signal.
If your problem is that you are getting poor connection between your wireless n router and a wireless n adapter, then, in the router, make sure the "Radio Band" is set to "Wide".
Poor wireless connections are often caused by radio interference from other 2.4 GHz devices. This includes wireless phones, wireless baby monitors, microwave ovens, wireless mice and keyboards, wireless speakers, and your neighbor's wireless network. In rare cases, Bluetooth devices can interfere. Even some 5+ GHz phones also use the 2.4 Ghz band. Unplug these devices, and see if that corrects your problem.
In your router, try a different channel. There are 11 channels in the 2.4 GHz band. Usually channel 1, 6, or 11 works best. Check out your neighbors, and see what channel they are using. Because the channels overlap one another, try to stay at least +5 or -5 channels from your strongest neighbors. For example, if you have a strong neighbor on channel 9, try any channel 1 through 4. For wireless n, make sure your standard and wide bands are at least 2 channels apart. For example try standard band on channel 11, and wide band channel 9.
Also, try to locate the router about 4 to 6 feet above the floor, in an open area. Do not locate it behind your monitor or near other computer equipment or speakers. The antenna should be vertical.
Also, in the computer, go to your wireless software, and go to "Preferred Networks" (sometimes called "Profiles" ). There are probably a few networks listed. Delete any network named "linksys". Also delete any network that you do not recognize, or that you no longer use. If your current network is not listed, enter its info (SSID, encryption (if any), and key (if any) ). Then select your current network and make it your default network, and set it to automatic login. You may need to go to "settings" to do this, or you may need to right click on your network and select "Properties" or "settings".
If the above does not fix your problem, download and install the latest driver for your wireless adapter.
Some users have reported improved wireless performance by switching to WPA encryption.
If you continue to have problems, try the following:
For wireless n routers, try setting the "n Transmission Rate" to 162 Mbps, and the (wireless g) "Transmission Rate" to 54 Mbps.
If you still have trouble, download and install the latest firmware for your router. After a firmware upgrade, you must reset the router to factory defaults, then setup the router again from scratch. If you saved a router configuration file, DO NOT use it.
Hope this helps.
Printer Sharing:  If the printer is connected directly to the router (by ethernet wire or wirelessly), then your computers need no special settings to share the printer.   The router will share the printer automatically.  However, a printer driver will need to be installed on each computer that is using the printer.  In some cases, you will need (or want) the printer to be set to a fixed LAN IP address.
If the printer is connected to a computer, printer sharing has same requirements as file sharing (see below).
File Sharing:  To share files, all computers must have the same "Workgroup name", all adapters (ethernet and wireless adapters) must be setup for "File and Printer Sharing".  Additionally, each computer must have at least one folder designated as "shared".
Pinging:  Pinging does not require the settings or setup mentioned in "Printer Sharing" or "File Sharing".  So pinging should work even before printer or file sharing is set up.
Message Edited by toomanydonuts on 12-09-2009 04:16 AM