Q: Greyish Smudge marks behind the glass screen.

Same thing here on my 27" i7 refurb. Upper right hand corner. Glad I found this forum, but pathetic there is even a need for one. Seems like cell-phone maker Apple just dosen't make good computers anymore.

I've replied many times to this thread. I've had my LCD Panel replaced four times; twice on a 2009 model, then I convinced Apple to replace the 2009 model with a brand new 2011 model because we thought the problem was my unit, then again last week on the 2011 model. FOUR TIMES.

I have AppleCare for two more years and intend to have Apple replace the LCD the moment I see the greyish smudges (which are NOT dust, they are burst LCD cells despite the claims of some people on this thread.) and, as is my right under Apple Care, I'll have them do the repair in my home so it only disrupts an hour of my life rather than 3-5 days.

How do I know it isn't dust as so many are claiming? Here is why:

1.) A repair technician replaced the LCD in my home and said "Yup; that's burst LCD cells." Then he proceeded to remove the LCD and I took picture of the interior. While it had dust he commented on how little dust there was inside my unit. I said "Well, I have a severe allergy to household dust. We dust weekly plus we have an expensive air purifier only 3 feet from the iMac." I'm a non-smoker and an anal-retentive clean-freak. Between my known habits and the remarks of the technician it is clearly burst LCD cells due to overheating.

2.) As the technician said "If it were dust I wouldn't replace your LCD panel. These cost $450.00. I'd clean it and put it back in."

3.) One of the Apple Store techs had previously confirmed it was burst LCD cells. That's why they replaced the entire iMac for free with a newer model. They had heard a rumor of a heat shield and thought moving to a newer model would solve the problem.

If you do not have Apple Care you have a helluva fight on your hand. If you do have Apple Care then use it and use it often. The only way Apple will resolve this problem permenantly is if it becomes too costly to repair all our systems again and again and again.

Thanks HP. I intend to do the same. Why should I pack-up a 27" 30lb. computer when I can call a local Service Provider and have them come to me. I do have the extended Apple Care for my computer, and will use it often also. Just as other have said: Nobody smokes in our home or around the iMac, desk and office are always clean and dusted.

I just can't believe how a company that blows their own horn for design excellence so much allows crap like this to be sold. Oh yeah, now I can: $$$$$

Just received my 2009 27 inch I-Mac back after my fourth repair (LCD panel replacement), I had read on these threads that with Apple Care the technician would come to your house (something I was not aware of previously), the Apple Care advisor, however, told me that they "will only come to your house if they know for sure what is wrong, so that they don't bring the wrong parts" I thought he was joking and tried to kick it up a level and got the same response.   Either way my panel has now been replaced for the fourth time and the store told me that if it happens again I likely will get a new unit, they're still acting as if they've never seen this problem and that I must be doing something wrong, e.g., smoking, dusty room etc., etc...  I've also found out that without Apple Care the cost so far would have been in the mid $600s per repair, so to date I'm looking at >$2400 in repairs on a $2500 computer, at least the close to $300 I paid for Apple Care was a well worth investment...

No way.  They have always come to my home to fix whatever was wrong.  I have been asked, on occasion, to bring it to an Apple store, and I simply tell them that I want them coming to me.

I too had the very same problem with 3 iMac's (including A Mid 2011 iMac 27" ) All got Grey Marks on the screen. I have Just sold on the 2011 iMac Because this fault keeps happening and it appear's this has happened to so many people. I even found many Web site Petition's on it that described the problem in Detail.

Will NEVER BUY ANOTHER iMAC ( Due to this design fault with the screen's )

I am waiting to see if Apple update the Mac Pro because i don't want to buy another Apple Computer with a built in screen i can not replace myself , Hence the Mac Pro Ticks all the right boxes.

If They Don't Replace the mac pro in 2012 then i am sorry to say - It will have to be a Hackintosh of some description or Even Dare i Say it " WINDOWS PC "

Now that's really  Scary i thought i would never have to say that.

I Think Apple OS X Lion  is Absolutly Fantastic but the iMac is a Real Lemon & Apple should Acknoledge this fault and put a program in place.

Wow - a lot of posts magically disappear from this thread. Thanks Apple mods for deleting things that bring out the truth and/or help people with the problems they are experiencing with your flawed product. Just keep up the black hole of disinformation.

I am experiencing this on my iMac - my first Apple computer.   You will find many people that think this is simply dust behind the glass. Others that find it to be dust inside the display panel (not accessible without a massive deconstruction) and others that site it as exploded pixels.

I dicovered my smudges just after the warranty expired.  I don't recall if I purchased Apple Care.  Either way as you read through the thread, you'll see I'm in for a fight AND the only fix they can offer is temporary.  Apple and its employees are treating this like the US Government treats Area 51 - it simply doesn't exist. Take yours to an Apple store and you'll see -- they've never seen anything like it and it must be because you live in a really dirty/dusty house.

If I get mine fixed I will be selling it IMMEDIATELY and very, very, very reluctantly buying a new HP at Costco.  Super sad.

Not sure what posts you are seeing "magically disappear", but the only ones I have seen go away are ones that are attempting to drum up support for a law suit or other legal action. Those are not "things that bring out the truth and/or help people with the problems they are experiencing". They are just stirring the pot, or if you prefer...trolling.

If you purchased AppleCare, you can check your user profile and/or ask at the Genius Bar. It may be also that many employees indicate "they've never seen anything like it", it could be because they haven't. While there are over 700 posts, that isn't an indication of an overwhelming number of problems. I don't have this problem, call me lucky or anyother name you want, but this isn't anywhere near the huge problem you, and others posting here, want to make it out to be. Granted, if you have this problem, your sample is showing a 100% sample rate. But add mine and it is down to 50% in a hurry, then add the thousands of others....do the math.

Now, get off it about Apple pulling posts about legal action, what do you expect them to do? If they were REALLY trying to hide things, this whole thread would have been pulled 2 years ago when it started.

There shouldn't be a pot to stir.  I love how peoople like you argue that it's so insignificant and then turn around and ask what I expect Apple to do.

What do I expect Apple to do? 

I expect Apple to stop producing and selling these expensive units with this design flaw.

I expect Apple to inform it's store employees (or at least its geniuses) of this problem.

I expect Apple to replace affected units without a hassle.

I expect Apple to stand behind their product.

I do NOT expect Apple to ignore the problem, delete posts, frustrate buyers, leave its employees to speculate about this problem, tell people it's their fault for having a dirty house or whatever else they are doing other than fixing the situation.

To your expectations...

1) Not going to happen, because this is a, statistically speaking, a fairly uncommon failure. It does not appear to be a "design flaw" to me, because if it were, it would happen to many, many, many more people.

2) How do you know this hasn't been done? Because the few people you have spoken to haven't seen it? You ever tried to pass information to the numbers of people we are talking about around the world? It didn't happen when I was in the Army, it will never be 100%

3) If there is a problem with a unit, Apple will repair it under warranty. Their typical process is that if a unit needs repair a number of times, varies from what I hear from 3 or 4 up to as many as 6 or more...

4) They provide a warranty and will repair it if there is a defect.

And finally, they are not ignoring the problem, there have been posts here indicating it has been addressed by executives and/or their reps. The only posts I have noticed being deleted are ones that violate the Terms of Use. How do you know that some of the problems are NOT related to local environment? Have you ever seen a computer that has been in the house of a smoker? Frustrate buyers? That one is on you...you let yourself become frustrated.

I am done, Apple will continue to pull posts that are in violation of the ToU, you want your posts to stay...don't post in violation of the ToU.

@RDJ2011 Thanks for the link. I had never heard that guy's story. It's very disturbing.

Everyone who comes here, please subscribe to the thread and make sure you get email alerts. That way you can read anything that Apple decides to censor on here.

@J.K. ROFLing I'm happy your iMac is in great working condition, but it doesn't mean it's going to stay that way. I've had mine since late 2009, and this grey smudge issue just started happening. You might also have a yellow screen tinge that you're not aware of. You should check macrumors and do a screen test. I've found most people don't actually recogonize the yellow tinge until someone points it out to them on a grey screen.

Totaly agree with Motofabio.  He has listed exactly what I expect Apple to do.  I have spent thousands and thousands of pounds on Apple equipment over the years and have found them to be extremly reliable and well designed and built.  I am therefore dissappointed in the problems I am having with my 27" iMac screen.  I never took out Applecare as in my experience I have never needed it so that is not a solution for me as my iMac was out of warranty before it started showing these screen problems.  Many of my friends have iMacs and they ALL now have these screen problems, so I don't think the problem is as rare as J.K ROFLing imagines.  It is a desgin issue as my iMac 24" dosn't have any problmes at all and is in excatly the same envirnoment (and two years older) so does need resolving and I think Apple should do the right thing by their customers.

I had a first generation iPod Nano which was working fine yet Apple replaced it with a brand new Nano. I thought this was truly excellent service.  Though  I assume as there may have been a fire hazard that this may well have been the reasoning behind it.  However many months after it I am still coming accross people who never even knew about the replacement program.   I never came accross threads with over 700 posts complaing about battery issues in their Nano's in the first place.  So I reckon 700 posts is a fair indication that there is a significant problems with iMac screens.   I am certain there are many more iMac owners with the same symptoms who will not be aware of this thread.  It took me a while to come accross it when I was trying to figure out the problems with my screen.

Hope the next iMac range is better desgined as I realy need to upgrade my system and still like my Apple products.  Reckon I'll be taking Applecare out next time. 

I just deleted a huge reply, as I am now done with this thread as well; you can continue to make all the excuses you want for them.

I don't have all the right answers; ignoring a relatively small group of users is the way to conduct business when money is the ONLY motivation.  I don't think this is the response Steve Jobs envisioned when he said "Go for perfect."

motofabio is absolutely speaking the truth. I think money is becoming the sole motivation at Apple.

@J.K. ROFLing I feel sorry that one day your iMac will suffer the same fate. And I'll say it again, this is NOT an issue that can be solved by a simple screen replacment. It is a hardware defect, and it cannot be fixed unless the entire machine is re-designed. I've seen several people on here, including me, who have kept their Macs in completely pristine conditions. So saying this is purely enviornmental is just plain ignorance.

I'm convinced the only way Apple will recall these machines is if they start bursting into flames. But otherwise, I expect they will just ignore this entire block of iMac users, especially since they are possibly readying a new redsigned iMac for release sometime this year.

Have a new Mac pro book. All is excellent. Also thinking about an imac, after reading the posts, maybe not. I live 250 miles each way from a Apple store or genius bar. I need to fed ex the system, then wait, email or phone or something. Will put off buying the imac for a while. I live in the NW Rocky mts., computers wait for summer to dry the gravel and dirt  roads. And worse, the dust is terrible here with summer pollen.