I too have issues only with Lion.
I have an assortment of machines here all running SL or iOS and they all function flawlessly and have no wifi connection issues. However, the two machines that I installed Lion on are both dropping connections and having difficulty seeing the rest of the network. It should be noted that of these two machines, one is 5 months old and previously ran SL without a single glitch, and the other one is brand new as of yesterday (8/2/11)
So in my case at least, resetting PRAM or SMC is pointless as this defect is seen on a new Apple Store bought unit.
There is also an issue that I alluded to with Lion having trouble sharing with AFP, but that is a discussion for another thread. In any case I sure hope Apple is listening and queuing these bugs to the top of the QA list for a patch sometime very soon!
I too had wifi issues when I installed Lion but I have now solved them. (Well, made them go away!). This is the sequence of events:
1) Running Snow Leopard: No Wifi issues.
2) Installed Lion over Snow Leopard: Wifi would drop out, fail to reconnect after waking from sleep. No other problems.
3) Wiped hard drive, installed Lion from scratch (using boot disk I created), restored from Time Machine backup: Wifi problems lessened, but lots of other little problems surfaced.
4) Reinstalled Lion again, over running system: No problems AT ALL. Wifi now actually reconnects faster when waking from sleep that SL did.
Hope this helps. Andy.
Ok, I've done it now for the second time. The Problem seems to have something to do with the migration manager.
Here is how I did:
Make yourself a Boot DVD or USB Drive. (USB is way faster....you can create the DVD anyways, but I recomend to do it with the USB Drive. I did it with an 8GB wich was well)
To do that you need to redownload the Lion installer from the App Store. (I recomend to put your Mac somewhere near the router, so that you can connect a cable. It only took me 30mins to downlad Lion again, whilst the Wi-Fi because of its failure would need hours....)
How to download again?
Go to the Appstore -> click on purchased ->hold "alt" and click on the Lion App ->hold alt again and click on install. This will re-download the app.
When it's downloaded use this tool: http://blog.gete.net/lion-diskmaker-us/ to create a DVD or USB Drive
Don't forget to make a new Time Mashine Backup!!!!!!
If thats also done, restart lion, holding the alt key again. Choose the DVD or USB Drive from the boot options, wipe the harddrive, and install Lion again.
When that is done, DON'T use the migration manager. Copy all your needed Data manually out of Time Mashine.
And than Re-Install your Programs
That's how I did it now and it works perfectly.
I tried to migrate my data with the migration manager, but this caused the same Wi-Fi Problems I had before. If I make all my steps manually, there are no such Problems.
Just for your inof, I am not a tech geek or something..my iMac is even the first Mac I have.....but as far as I can say it, the Problems have something to do with the Upgrade from SL and the migration of some Data!
So far 2 days working with out error just by changing channel on router to 3 from 11? We shall see, but looks very good. I know we should not have to mess with routers, but I changed the channel and rebooted it. Everything seems ok.. I will keep you posted. '
This was very easy and seems to work, it also will not effect any ohter devices.
Hi Stefan... I'm a big Mac fan and sometimes zealot, and I will tell you, the problem is real.
Apple, no doubt, will release an update to fix it soon.
Meanwhile, please try the "ping" solution listed elsewhere in this forum. I'd repost it here, but I've done so more often than I think anybody will soon be willing to tolerate.
It works. .
At least, it's the one that most people seem to report as working. I didn't come up with it, another user did. I've just been doing my best to propagate it, after it completely solved the wifi-dropping problem for me.
And it takes about two seconds to do.
Search in this forum... you can use my name or 18.104.22.168 as a keyword... if you still can't find it, let me know and I'll repost for you.
I was an "early me too" poster. My system was built from a clean install of SL, followed by a download from the App Store of Lion. Immediately after the Lion install completed the WIFI connection dropped even though I was feet from a new Airport Extreme running in dual band mode. I noticed that "ifconfig -a" would sometimes show an IP address on the interface and sometimes not - even though I had full bars and fully connected.
Re-ordering the Service Order in the Network Preferences seemed to fix it - and it worked for days after doing this, but yesterdau it was back and the only way to keep the WIFI up was to open a terminal and ping the router.
So, I decided to do a clean install of Lion from a boot disk (extracted from the Lion Install App). I booted the DVD, erased the hard drive, and completed a fresh, clean install. After the installation finished and when the installer prompts for your Apple ID I started seeing the problem - it could not talk to Apple during the registration phase.
I've tried all the other suggested "fixes" - none of them work - the only thing that seems to keep the connection up and working is a constant ping to the router.
So a fresh clean install of Lion with nothing else modified still brings the issue up.
My next step will be to pull my old Airport Express (G no N) and setup a new network with it - I have a hunch this has something to do with the dual banding of the Extremes.
I believe Apple is seriously looking into this because they called me - I did not make a service call - they called me - so maybe a "real" fix is on the way?
Not a dumb question at all. It is setting on the router itself. All are different, refer to the manual for your router. The settings are usually accessible via a webpage held on the router itself, accessed through a browser.
In my experience this may help the problem, but only if it is caused by other devices/routers nearby operating on the same or nearby channels. Could be worth a try though.
As pointed out by AJ Matheson, you will need to access your router's website; the URL usually starts with something like 192.168.x.x or similar. Once signed in, you can change all sorts of settings and, usually, changing the channel is recommended especially if your router operates at 2.6 GHz (which is also where most phones, microwaves, etc. operate). In fact, there was a post here not long ago that showed that turning off a baby monitor restored the wireless reception on the Mac. So, aside from checking which channel you are using, you might also want to check your other household devices. FWIW, if your router is an Apple Airport model, the settings can be done on the Mac (I believe; I don't have one - mine is a Netgear). As an example, here is the channel setting for my Netgear on their website:
I wonder why changing the channel helps!
If everything was OK before Lion (i.e. Snow Leopard) what has happened in Lion? Perhaps there are certain channels that are known to work better than others.
It seems to me that people have experimented and found a channel that works for them. What I'd like to hear from Apple is a definitive statement that tells us what channel(s) to use.
Assuming, of course, that that's what the problem is (which I doubt).
You'll see that answered in the other ping posts, but it's easy... Most who are writing in say that the dropped signal is not instant. They get a few minutes of connectivity after a router reboot.
Before entering the ping command in Terminal, unplug and replug your router and wait about 30 secs for it to reconnect. You should have a soon-to-be-dropped wifi connection. Now enter the ping command in Terminal and let it run. If you,re like most, the dropping should stop.
As an update to my saga as an early Lion adopter with the annoying Wi-Fi frequent disconnect problem, my original machine (iMac 27" Late 2009) has demonstrated enough Wi-Fi connection stability (after router FW upgrade) that I decided to upgrade my MacBook Air (11" Late 2010) to Lion as well. I have experienced no WiFi drops for 3 hours.
However, I have now noticed something that is very strange and this information might be useful to others. Another earlier poster commented that the new Wi-Fi Diagnostics tool was reporting that his US made Linksys router was Country Code TW. At that time on my iMac, I observed the same behaviour. After today's upgrade to my MBAir, I immediately started up Wi-Fi diagnostics and it too reported Country Code TW. I wanted to compare Signal and Noise measurements with my original iMac and was surprised to discover that it was now reporting Country Code US (not sure when / how it reverted from TW). I have verified that both machines are communicating with exactly the same router transmitter (I have a dual band N router Linksys WRT400N firmware 1.0.02 Build 11). So, the net is that the iMac has demonstrated stability with this setting (which I cannot figure out how I can control / change). I will have to observe my MBAir to see if the TW setting indicates less stability of WiFi connection as I am only suspicious at this point.
I am not a networking professional so I cannot definitively say that this is a problem but from the layman's point of view it cannot be right. Hopefully, this will be a clue for someone else to build upon.
What I'd like to hear from Apple is a definitive statement that tells us what channel(s) to use.
I'm not a networking professional either, but there is no way Apple (or anyone else) could do this - that is why there are so many channels. It is your environment; companies can only recommend certain ones, but unless someone were to come to your home and check your setup including your other devices, walls, any obstructions made of metal between router and Mac, etc. you won't be able to get a definitive answer. You can maybe get your ISP to come out and troubleshoot - in my case, Comcast tech suggested I try 11 (even though I had no problem connecting, but he tested faster download speeds with 11 rather than 6 which is what I had it set at).