27" imac wifi problems (intermittant)

I read on another forum that the problem still exists in mountain lion.

I cannot confirm this.

But I see my network but when I try to connect no way. The macbook's ipad and iphone work fine.

Sad that so many ar efacing this problem. Allthough a college of mine upgrade from snow l to lion 10.7.3 not 10.7.1 .... 10.72. and so on had no problem.

:-((

Still having problems with this..... WE NEED A FIX APPLE.

My Wifi is fine on every device but the 27" imac. And no, it's not my router's problem.

Any updates?

I've been reading this topic from start to end after running into the same issue, wifi dropping out occationally without any issues on Android or MS devices. Also, Bootcamp on the iMac works fine. I think I've found my solution.

Another poster wrote that this issue might be caused by frequent change of channels by the router, wich continously searches for the channel with the least interference. This can, during heavy traffic in my block, make my iMac confused as the channel changes too often for the iMac to follow. I'm not a programmer, but it seems plausible.

I downloaded a neat little thing called iStumbler (http://www.istumbler.net/) that searches and displays all close proximity networks around me, and wich channels they are on. Most likely many of them will be configured to automatic channel scan. I went to my routers settings (192.168.0.1 in the browser) and disabled automatic channel select, forcing the router to communicate on channel 2, at the present time the channel with least interference where I am.

At the moment I haven't had a single dropout since I applied these settings some hours ago, compared to at least 8-12 outages in the same period of time the last weeks. Supah jinx, but I think this works!

The forced channel select should take care of the dropouts, but make sure you connect to a channel that can provide good reception for your device. You can monitor this in iStumbler along with all the other networks.

I hope this works for you guys!

Yes - I did this ages ago. It certainly helps, but it is not a cure for the problem (though I did have a period of several weeks after changing to Channel 13 before the drop offs started again).

Incidentally you don't need any seperate programs to do this trick: Just go to "About this Mac" in your Apple menu (Top left of screen), click on "More Info" and then on "Airport" - you will get all the details of the channels being used by other people nearby, signal strengths, your Transmission Rate etc.

I'd like to add my name to the long list of Apple users having this problem.

Bought my iMac 27'' December 2011 in Germany. It occasionally dropped off my home WiFi connection, but the problem has become worse over the past few weeks (since the supposed update in early March).

Now it looses Wifi (from trusty Airport Express router) about every 15-30 minutes, requiring me to log on again. This is completely unacceptable!

Let's hope you'll find another solution. So far we've had extencive internet traffic in our appartment on several devices (iMac, 2x MacBook Pro, Win7 laptop, 2x Sii, PS3 and Galaxy Tab) without any dropouts on the macs. Neither have we experienced any reduced performance according to Speedtest.net.

So I'd be happy to change the channel after a few weeks if the issue should return, its a pretty quick fix.

Can someone please tell me what I should tell my client that have this problem? To never buy a Mac again?

What the f*k is happening Apple?!? 😠

Hi

I have now read over 70 replies ( equating to 70 other people with wifi problems ) and I conclude the following:

There is a wifi problem with the new imac 27inch.

I have both a 21 and a 27 running lion. Both 8 months old.

Problem started on 27 inch and not 21.

Its nothing to do with my router, ipads, iphones or my other PC's in the house.

Apple know there is an issue, but this ones is fast turning in to the Iphone 4 grip of death saga.

No one should accept waking up a $2000 computer by pressing the on off button... the software is not working and they seem to have difficulty getting it corrected.

...oh and I have all the latest updates.

When I am asked if I would recommend imac to people... i would have said yes before this crappy problem started.

Dear Apple,

the measure of a problem is how you deal with it !

your customer!

I just called Apple Support and was told to switch off my iMac 27'', unplug all cables, press the on/off button for 6 seconds and then start up the mac again while holding alt+cmd+p+r

Unfortunately, this didn't help - wifi just dropped again...

Apple, we need a fix fast!

I just got off the phone with Apple Support. Tech guy emailed me a link with newest patch (about two weeks old). We'll see how it works.

You mean the two week old patch which is two weeks old - and has been found not to work by numerous respondents within the last, um ... two weeks ? Do we really need to retread over the "change channel", "download software update which might work" posts EVERY week to "see if they'll work" when a simple read over the last 1 page of posts will answer the question ??

Thank you for your input and valuable advice.

Actually the problem was your lack thereof - but you obviously haven't read through any of this thread yet - trust me ... you will.

K After reading through the thread I would like to share my problem too.

I bought my 27" imac in July 2011. Ever since day one i had that problem with wifi. The connection would randomy drop and i had to turn off my WIFI and switch it on agian. It bugged the **** out of me and i have spent few hrs with apple customer service trying to resolve it. They said its gotta do with my router channel setting.

Lucky in Jan 2012 I changed my router to a Rogers Cisco Modem/Wifi Router combo unit. Ever since then this problem was resolved.

Now recently i have a new problem. My iMac doesnt get the internet speed its suppose to. Speedtest.net shows i get about 3.26 MBPS up and 1 MBPS down. Where as on my ipad from the same location and wifi connection I get 21.77 mbps down and 1mbps up.

I really think i have a problem and i even took it to the apple store. And all they did was a system diagnostics and told me everything seems fine and sent me back.

Anyone having problems with speed?
How do i handle this situation?
I have still under my 1 year warrenty and i also have Apple care.

Thanks

This is an Apple problem through and through. It has nothing to do with what channels other wireless routers are on or the position of the aluminum case. The only time the wifi operates reasonably well is shortly after I restart or start from a full shut down. Performance degrades from there. Often the network diagnostics show red lights for ISP, Server, and Internet. Occasionally, Network Settings gets the red light too. But other times I am fully greelit on Network Diagnostics, but when I check the Activity Monitor there is a zero rate for sent/received or some ridiculously small number of bytes. From the many bizarre and arcane proposed solutions I have seen suggested, the only thing missing seems to be human sacrifice. Now why would I say such mean things? Because PCs running on the same wifi system operate at roaring speed. And I am thoroughly infuriated because like all the opther unfortunate posters, I bought an iMac expecting a better experience that a Dell would have provided. I have read numerous posts about this problem, and the glaring thing that is missing is an honest response from Apple in which the company admits responsibility and offers to fix or replace the many defective products they have pushed into the marketplace. Very, very disappointing. Just another corporate one-finger salute to consumers.