When on internet my iMac keeps going to gray screen with message reading 'You are not connected to the internet'. My wireless connection is fine for my other devices, why does my iMac keep losing connection with network?

Question

I have read other post about this and one of them said to uncheck "enable auto channel scan" in my router settings and chang from chanel 6 to 5.  I was able to change the channel to 5 but i can't find anywhere on their page where it has the option to uncheck "enable auto channel scan".  I have a Netgear router WGT624 v3.  Can anyone recomend anything?

Answer 1

I've had this problem for months and finally called Apple support and paid the one time support fee to get a solution.  I purchased a 21.5" iMac in the summer of 2011 and am currently running OS X 10.7.3.  After confirming all my wifi settings were correct (already suspected this, since every other wireless device in the house works great), the Apple support tech recommended changing channels on my router from "Enable Auto Channel Scan" to one channel out of the 11 available.  I currently have a D-Link DIR-655 router, but the tech said the same structure exists on all wireless routers.  In other words, my situation would not improve if I bought an Apple router (Airport Extreme, Time Capsule, etc).  I logged into my router (here are common IP addresses for routers...  http://compnetworking.about.com/od/workingwithipaddresses/f/getrouteripaddr.htm , and made the channel preference change (in my case, unchecked "enable auto channel scan" and changed from channel 6 to channel 5).  It's been a few days since applying this change and so far, I haven't lost my connectivity. Even though I live in a residential subdivision (not an apartment / condo), my iMac is detecting up to 21 other local networks and this was causing interference (some of my neighbors using the same channel).   Sure enough, when I check the channels of nearby networks, I find many are using channel 6 and no one is using channel 5.  To find out what nearby network channels are being used, go to Apple icon in top left, "about this Mac", "more info", "system report", under network choose "wifi", scroll down and see other wifi network info.  Changing the router channel from auto enable to a specific channel has improved both my internet connectivity and speed (not sharing same channel with neighbors).  Hope this helps!