Windows Vista’s Gamma Table Bug

Windows Vista has a new color-management/profiling format called Windows Color Systems. It purports to offer advanced color management and better results than the age-old (and forever dying) ICC/ICM color system. ICC has been buggy the whole way, with both political and technical issues plaguing its colorful history.

Windows Color Systems is a step in the right direction, but it comes at a very heavy price: Windows Vista no longer properly interfaces with ICC/ICM color profiles!

Anyone using the ATi Catalyst Control Center, BasicColor, ColorEye, Spyder, or any of dozen other color-management and gamma-correction programs available will have noticed the bug we’re talking about: once you lock your PC (winkey+L) the gamma LUT on your graphics card is reset.

ICC/ICM profiles have two different “parts” to them. The first is a color-correction section which “maps” the colors produced by the video card to match the correct color output as defined by your monitor. “Blue” on your monitor may be different from the “blue” on your mother’s – that’s what the monitor-calibration and gamma-correction software seeks to fix. Once you “regulate” the colors on your PC, you’re using the “real” blue, one that the color industry has reached a consensus over.

The second section of the ICC regulates the gamma output. In order to make certain colors match up, the gamma (more or less the amount of black/bright your display shows) is modified to tally-up with the correct settings. With properly-calibrated monitors, an image will display (almost) exactly the same – with the same hues, midtones, and shades; with the same brightness; and the same overall effect. Gamma plays a very important part in this, regulating the highly-varying brightness/contrast settings on monitors to produce the same image in the end.

With Windows Vista, when you first load an ICC profile, the correct color and gamma settings are applied. But when you lock the screen, log off, or do a bunch of other things, the gamma LUT is reset. The correct colors are still applied, but depending on your configuration your display might now be a garishly bright hue of green or blue!!

There is no fix, at least none that we can see. We’ve tried to apply the ICC profile to both the local account and the default system settings, we’ve disabled UAC and formatted and reformatted. We’ve tried it on nVidia and ATi, and it always happens: when you lock the PC, your gamma table is reset.

Microsoft has not yet acknowledged this issue (as a quick search for “gamma” or “ICC” in the Microsoft knowledge-base will reveal), but there is a workaround (though a poor one). The freeware DisplayProfile utility (donate to help cover hosting costs!) will show you a list of available ICC profiles and let you switch between them on the fly, but more importantly, it will also apply the gamma table settings as well.

DisplayProfile is a standalone executable. Just run it and select a profile other than the one you want to use, then switch back to the real profile in order to re-apply the gamma LUT settings. Just stick it in your quicklaunch toolbar, and whenever you unlock your PC run it to reset the gamma settings.

Hopefully Microsoft will address this issue with Windows Vista SP1 later this year. Until then, thank God for freeware!

132 thoughts on “Windows Vista’s Gamma Table Bug

  1. Thanks for your help; however the link for DisplayProfile doesn’t seem to be working. It redirects to “” and then gives a 404. Can you help me out? Thanks.

  2. Thank heavens I found this blog article, I’m currently being driven mad by Vista on one laptop resetting the LUT after sleep/lock/UAC and finding hardware calibrator useless. Still haven’t found a stable solution so have drawn the same conclusion, a bug in Vista or graphic driver implementation.

  3. Arthur I wish is was using either of those. This is happening on a Sony VAIO laptop using an on-board Intel GMA950 graphics processor.

  4. Hmm… Andrew, that’s one of the most “un-buggy” drivers out there, ATM – at least in our experience. The Intel drivers are pretty cleanly written (and open-source for peer-review)… To be brutally honest: they don’t do much, so it’s not too hard to write them right πŸ˜‰

    In that case it seems to be more likely a Vista bug than not.

  5. That’s what I thought Computer Guru given how common the Intel GP is. I guess we can all live in hope that MS will take a peek under Visat’s hood to see what’s going on…

  6. There’s been a lot of to-do regarding Vista’s propensity to kick out the user’s active color profile on certain system events. This issue certainly has bugged the hell out of me.

    I’ve found that plugging in or removing a USB device, opening Outlook 2007, having the Windows UAC dialog displayed, and several other various system events will cause the whole color profile to get whacked. I’m running Vista Home Premium on a Toshiba Dynabook, with a Mobile Intel graphics card – fairly run-of-the-mill.

    I’ve found a short-term solution that seems to work well enough for now. at least in the short term until the color management features of Vista itself are properly corrected. I’m now using Huey, a color calibration USB tool that has an automatic room lighting calibration background utility. Even if various events in Vista do clobber the calibration, I’ve found that you can set Huey’s room lighting recalibration for as short an interval as every 10 seconds, and the color settings are recalibrated without any need for constant user supervision and intervention. It seems to be working well enough for now, and at least saves me the trouble of having to stupidly reset the color profile myself (doi!) every time Vista whacks it into la-la land :8

    Incidentally, the LUT and color management issues on Vista are getting to be a big problem for a lot of people. Not only on this blog, but also on Adobe forums there has been some to-do about simialr issues with Adobe Gamma. I’ve also found several other people complaining about the problem through a Google search as well. I hope that someone at Microsoft is listening – there are apparently a lot of unhappy graphic designers and gamers out there who found out about this the hard way.

  7. I have headache with settings gamma on vista and multiple monitors. Once I tried powerstrip (annoying 5sec startup) and then RivaTuner.

    Rivatuner v2.04 has feature of gamma settings. So install riva tuner, set gamma to default and check “set this value on startup”.  (Or you can do this manually everytime vista set their gamma)

  8. Yeah, but that’s such a headache!

    I never had a problem designing on Windows, even when all my friends literally begged me to move to Mac – but this really has me going up the wall… I shouldn’t have to so anyhting at all to make my gamme settings stick…. should I?????

    I’m sorry, I really am, but what kind of crap OS is this, anyway!?!?!

  9. Has this been resolved? I’m having this problem on a Compaq with an Intel 945GM express. DisplayProfile.exe doens’t let me change profiles, just gives an error message–there are multiple profiles to choose from but I can’t change to any of them. Are there any other workarounds?

  10. I’ll give that a shot… it’s not my computer, and I’m not so great at Vista yet, so it didn’t occur to me to check.

  11. OK, running as Administrator doesn’t help, either (but good thought!). I still get a pop-up that says “Error -XXXX” when I try to switch (I forgot the number, sorry, but I don’t think it would be that informative).

    Incidentally, none of the profiles that were there had an asterisk after them which would seem to indicate that they contained a gamma table tag.

    I tried installing a new color profile as detailed here: , but that didn’t appear on the list, and for all I know could have been something else entirely.

    I also tried looking around at the color profiles by opening the “Color Management” configuration utility, but I’m pretty far out of my league here, so I was hesitant to go around switching defaults and whatnot. Plus, if it truly is a semi-hardware thing (i.e. the lut getting switched on the card) then I doubted that any of that would work.

    I’ve also looked around on the internet but haven’t found anything other than references to this article. (And of course there’s nothing in the MS KB, as you said.) I’m truly grateful that there are people like y’all who notice and think about these rare and arcane bugs.

    Do you have any more ideas?


  12. Well, the UAC didn’t work, but thanks for the suggestion. Any other ideas? (I had a longer post, but it was flagged as spam–maybe an admin can post it for me? Sorry!)

    And thanks for your help!


  13. Hmmm..

    They need to have asterisks after them to be of any use, so I don’t know.

    Actually, I’m a bit confused here:
    If none of your profiles have an asterisk after them, I’d assume you wouldn’t experience this bug in the first place because there isn’t anything to get reset – they’re all “blank” gamma profiles, so to speak; so your LUT is also empty, and therefore, not really at any risk.

    Can you describe your problem in greater detail?

    Make sure you’re using the latest version of the video card drivers, though I don’t know if it’ll make a difference.

  14. Ack! Perhaps I have a different problem then and have been barking up the wrong tree this whole time. The symptoms are the same: one day (not sure what the immediate circumstances were) the colors got all out of whack and acquired a rather garish blue tint to them. The video driver was the first thing I tried, of course, but it had no effect. After much googling this was the only possibility I’ve come up with, as there seem to be no known issues with any of the hardware and Vista as far as I can tell. (Compaq Presario C500 laptop.) Very frustrating, but now I’m determined to find out what it is!

  15. That tool didn’t seem to work in Vista (installer quit with no explanation). I messed around with the gamma settings in Color Management but couldn’t get a satisfactory result: though I believed that it was just that the blue gamma was too high (white appears as blue, for example) just messing around with the brightness/contrast/etc couldn’t quite fix it, so I’m suspicious that it might not be a gamma issue after all. I realize that I’m not giving nearly enough information for a diagnosis, but it’s a very hard effect to describe without seeing it–white appears as blue, black appears fine, but dark greys appear slightly reddish (and the other colors are all off). Do you have any other suggestions for places I could look around to try to find other possible problems that might result in something like this?

    And thanks again for your time!


  16. OK, I booted it into Knoppix and the problem was still showing up, so I figure it has to be hardware now. Sorry to sidetrack y’all on this, and thanks for all your help!

  17. the issue with the ICC profile being reset (even if it is listed in color management and activated)in some conditions (reboot, graphics settings change, sleep, etc….) is still there. It is surprising that only a few people noticed the problem when it occurs on ALL VISTA editions.

    Looks like most people are not using this feature or they are blind.


    Today December 11, 2007 Microsoft didn’t fix at all the problem. Vista is poor software.

  18. I have a problem that when i open pictures taken by a Nicon camera on a Windows Vista OS the images have sort of a blue background. The same images on other computers running XP appear perfect. To your knowledge does DisplayProfile solve this problem too?

    thanks for your assitance.



  19. Good news everyone: it looks like this bug has been patched in SP1.

    I’m actually running Windows Server 2008 Nov. CTP right now, which should share the same codebase as Vista SP1 – just finished calibrating my monitor, and the gamma profile has not been reset by locking the screen or hibernating.

  20. Excellent news – I’ve confirmed that with the installation of Office 2007 SP1, now the gamma is no longer reset when booting up Word, PowerPoint, Excel or OneNote 2007 on Vista. The gamma used to get reset EVERY TIME I booted up one of these programs. Offifce 2007 SP1 has repaired the problem, yahoo!!!

    This confirmed my suspicions that this is NOT a hardware issue, but it is a software-related issue, unique to Vista. 

    HOWEVER, this fix did NOT (and probably should not be expected to) fix the general Vista-related gamma reset problems on the user authentication control prompt, or when docking/undocking USB devices (even something as simple as mice, dammit!). 

    I am now updating Vista with SP1 RC – will keep you all informed on how it turned out. SP1 RC is now available through Windows Update (it’s a little tricky to download, though). Here’s hoping for the best…



  21. I’ve installed Office 2007 SP1 and still have the reset problem whenever Outlook has opened and started to download messages. I wait in anticipation for Vista SP1 reports…

  22. O.K., guys, now for the bad news: Vista SP1 did NOTHING to solve the gamma reset problem for me. It took over two hours of my time to go through that ordeal, and… nothing. Zilch. Bug squat!

    I also am starting to wonder whether Office 2007 SP1 had anything at all to do with the gamma problems. I checked out Microsoft’s list of all of the bazillions of items that were fixed in Office 2007 SP1. Not a single one had anything to do with display gamma or color profiles. Nevertheless, my problem seems to have been solved for Office 2007.

    I must also admit that when I downloaded Vista SP1 RC, I installed all of the other available updates through Windows Update for Vista. So to be honest, I really have no idea at all why the gamma problem got fixed for Office 2007. It was, however, the same exact problem that many of us have encountered with Vista.

    I also called Toshiba to see if there was anything they could do for me. (My laptop with Vista preinstalled is a new Dynabook TX66/A.) Basically, they treated me as if I was out of my mind. No one had ever heard of the problem, and apparently it wasn’t in their support database. They suggested that I reinstall the display drivers for Vista, which I had of course already tried and tried again. And get this: Toshiba’s “recommendation” was that I do a full system recovery and send my computer in to them for “analysis”. I asked how long this would take. They gave me a very rough guesstimate of 2-3 weeks, perhaps more. They said they would not supply a loaner PC in the meantime. I cordially replied that I would take care of things myself!

  23. Honestly – that’s that.

    You don’t have much left, in terms of recourse. Microsoft is not accepting any bug reports for SP1 for bugs that existed in RTM – basically, our role in the testing program is to ensure that SP1 doesn’t introduce any new bugs — nothing more, nothing less.

    It is up to Microsoft and Microsoft alone to decide if a bug in Vista gets addressed in SP1… and they’ve chosen to ignore a lot of these things are driving users crazy.

    Sending it in to Toshiba is a total waste of time, we’re 99.9999% sure that this is a confirmed Vista bug, all that’s missing is a knowledgebase article on the issue.

    Like I mentioned before, I never did experience it with Office 2007 so I have no idea what it was that fixed it for you.

    If this means a lot to you, go back to XP or another OS, because if SP1 doesn’t address this, you’ll have to wait until SP2: it is against Microsoft policy to hotfix/autoupdate minor bugs because they might break more things than they fix.

  24. OOPS.

    the problem I had with the ICC profile being reset at startup is not a vista bug.

    (correct profile was loaded by Eye1display 2 locader -or spectraview loader- then a few seconds later it was reset/removed without reason).

    The problem was with the nvidia startup driver file.

    If you are annoyed too, launch MSCONFIG, startup items, UNCHECK Nvidia compatible vista driver 1xx.xx and reboot (it doesn’t remove the driver but the nvidia gamma will not overwrite your custom ICC).

    Sorry (my english) I’m not sure it is a LUT problem as written in the original post.



  25. I believe Spyder2Pro uses the same method employed by DisplayProfile, so if you’re experiencing the ICC profile reset issue upon locking the screen or hibernating, it wouldn’t fix the issue.

  26. Well, it doesn’t kick the right profile after locking, log-off, or sleep (is that what you meant by hibernating?). 

  27. Well, as reported elsewhere, SP1 RTM does NOT fully fix this problem here. After a suspecd resume, Vista does eventaully restore the correct profile, but there seem other events that reset the LUT and Vista doesn’t spot it. Like pugging in a device (USB) and some othert events I’ve not got a conclusion on yet.

  28. I made an accidental discovery that plays-into all this, which I can’t explain, but thought someone would have some ideas…

    I bought a new Vista box a couple of months back, and never had any of the problems you all are experiencing (in fact, I thought you were crazy) – Custom profile with a Gretag MacBeth iOne, the loader would fire it up, and life was good (it never once reset).

    HOWEVER- The other day, I got a new monitor. The old one (a Sony) was running with the “Generic pnp” monitor driver.

    I merely unplugged it, and plugged-in the new one (a Samsung), and immediately, I began experiencing what you folks are describing – The profile would reset to a “bluish” thing a few moments after boot-up, every time the screensaver kicked-in, or I locked the system, etc.

    It’s important to note that other than swapping (physically) the monitors, literally nothing else changed – Same “Generic pnp” monitor driver, same nVidia card & driver – Even the same (incorrect) color profile I’d previously created for the old monitor.

    When I powered the machine down with the old monitor, it was perfect. When I powered it back up with the new monitor – All the pain you guys are reporting.

    As “nutty?” as it sounds…. It’s almost as if some kind of “communication?” with the monitor plays-into this?

    I’ll be interested in hearing what the gurus think.

    As a sidebar, I’ve since installed the driver that came with the new monitor (Samsung) instead of using the Generic one, and still, the problem persists. Also tried connecting the (old) Sony again, and the problem vanished!!! In my case, at least, this appears to definitely be tied to the monitor.

  29. John,

    No -I’m running the original Vista Home Ultimate that shipped with this (HP) computer, with all patches (several hours’ worth) applied (back in December).

    I’ve been avoiding SP1 until it goes “main stream” through Windows Update.

  30. Well, I hope they do this properly.

    On my system, the LUT gets reset not JUST when there’s an event that dims the screen. It will happen when there’s virtually any configuration change. Adding/removing a USB device. Or even adding/removing a network cable.

    Maybe this is caused by anything that forces the OS to refresh its device list. Then the LUT is reset when the OS checks the display/adapter is still there?!? But what do I know… Just my 2C.

  31. John, if you disable UAC do you still get this behavior?

    I know that I had it with UAC off (meaning the screen doesn’t dim in the first place), so I’m not sure if that’s an accurate description…. Unless, of course, Vista is stupid enough to attempt to dim the screen regardless of whether it’s actually going to prompt for authorization or not!

  32. I can confirm that I still get the same behaviour with UAC turned off. Seems like any system event forces the gamma table to be reset (and in some circumstances bizarrly even restored)

  33. Whenever I use the DisplayProfile program, I get an “Unknown Error: 5021” Response and it does nothing… Any tips?

  34. hellow sir, by mistake i delete adobe gamma from my computer. how can i reinstall it?

  35. Has this bug been fixed? I’m wondering because I’m NOT experiencing it. I haven’t installed Windows Vista SP1 yet, but I have installed all the automatic updates available up to this point. I don’t have Microsoft Office. I can’t say for sure whether it was a problem for me and went away or if it never was a problem for me – I haven’t tested it until now.

    This is what I did to test it:
    1. Adjusted my monitor’s color settings to be well out calibration by turning the Blue adjustment up. This is because when the display is properly calibrated the effect of applying a color profile is very small – almost unnoticeable, and I wanted to be able to tell distinctly when the color profile was applied and when it had been removed.

    2. Used Gretagmacbeth Eye-One Match software and the Eye-One Pro colorimeter to profile the display. This also tells Windows to associate the newly created profile with the display. As expected, this “corrected” the intentional mistake I made earlier of turning the Blue adjustment too high (at least as good as you’d expect for a software fix).

    3. Tried to get Windows Vista to clobber the applied color profile and was unsuccessful. I tried rebooting, sleeping, hibernating, locking the screen, User Account Control prompts, and inserting/removing devices.

    This is what I’ve got:
    Operating System: Windows Vista Business (Windows Version 6.0 Build 6000)
    Graphics Adapter: NVIDIA GeForce 6150, Driver Version dated 9/11/2007
    Monitor: Dell 2405FPW

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