Wireless crap shoot, why it has worked for years and now doesn't

Question

wireless dropped off last week. Did nothing, changed nothing to my knowledge. Now, have a cable modem from charter, so ethernet direct to my airport extreme. set up is good. but when I go to the internet, not connected. Assistant/diagnostics goes thru the same routine restarting everything, then says it can't fix the problem. So I am at this point...new cable modem, new airport extreme, and confirmed my wireless card in my macbook pro is good because I am able to join other networks. Geez.

Answer 1

OK, thanks. That confirms that the Internet connection is working and the wired portion of the AirPort Extreme is working, so we can concentrate on the wireless issue.
You may not have changed anything on your setup, but the explosive growth of wireless networks and other wireless devices like cordless phones and Bluetooth devices has created some Wireless Interference issues for just about anyone who is not lucky enough to live in an isolated area with no other homes around for a few hundred yards.
My neighbor...across the street...can literally bring my wireless network to a standstill if he is in his front yard talking on his cordless phone, so that might give you a quick idea of how wireless networks can be affected by outside sources. The link to the Wireless Interference document that I provided above will go into more detail about this.
Often, the only thing you can really do to try to improve things is change the wireless channel that your AirPort Extreme is using to see if you can find some clear airspace.
To do this, you would open AirPort Utility and click Manual Setup. Then click on the Wireless tab/label just below the Advanced icon. Try different Channel settings until you find a good, clear channel or run out of channels.