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“(Not Responding)” – What does it mean, and what do I do about it?


I am using windows XP PRO, and I am having difficulty when I am browsing or using a program. After a few minutes the computer freezes and I get a message in parenthesis saying (not responding). Sometimes I have to log off and log-on again to fix this problem. But after a few minutes it happens again. How can I fix this?

“Not Responding” appears in the title bar of a running program when Windows detects that the program isn’t behaving properly. Exactly why depends on the specific program and what you were doing at the time.

Let’s look at some of the possibilities which range from actual software or hardware problems, to user impatience.

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Windows expects a running program to “interact” with Windows, and respond to Windows’ requests in a timely fashion. If you type a key and the application doesn’t take it because it’s too busy doing something else, that could be a problem. Similarly, if you click on the Close Program “X” on a programs’s window, and the program doesn’t acknowledge that, then that too is a potential problem.

When Windows asks a program to do something, like take a keystroke or close itself, and the program fails to acknowledge that request within a certain amount of time, the program is “Not Responding”. If the program never comes out of that state, we might also call it “hung”, as in “hung up” on something.

There are “legitimate” reasons this can happen. For example, if the program you’re using is doing some very long, CPU-intensive calculation, it might not respond in a timely fashion. An example might be a graphics program performing a reduction or other operation on a large image. If, during that operation, you attempt to close the window and nothing happens, after a few seconds Windows might add “(Not Responding)” to the title bar to indicate that it has tried to pass your request to the application, but the app’s not listening.

Anything that causes the application to stop responding can cause Windows to add the ‘(Not Responding)’ moniker to the title bar.

While it might be considered bad form or bad design to not respond to user input or to Windows while performing lengthy calculations, it’s quite legal and legitimate. Once the calculation is complete, the program starts listening and responding again.

A recent real-life example of my own: earlier this evening I was working on a Visual Basic program that performs various database operations. I modified it to access a database remotely across the internet which turned out to be a mistake, because the operation became extremely slow on my DSL connection. While VB was accessing the database, it was unresponsive to everything else. Windows tagged it as “(Not Responding)”. Since I hadn’t saved my program to disk (bad form on my part), I was loath to just kill it and lose my most recent edits. So I just let it continue while I did other things. An hour later the operation completed, and VB became responsive again.

Anything that causes the application to stop responding can cause Windows to add the “(Not Responding)” moniker to the title bar.

So while lengthy calculations are one semi-legitimate way it could happen for a while, what are some of the other things that can cause it?

  • Programming Error – the classic case of an “infinite loop” in programming is perhaps the most common example – if an algorithm is mistakenly written such that it never ends, and within that algorithm Windows is never given a chance to operate, the application may become “hung” and unresponsive. As a user of the app, there’s not much you can do here except avoid whatever it is you did that brought the application to that point.
  • Software Design Error – really just a variant of the preceding point, but I think of it as a different class of problem. The example I see from time to time is a program that displays an error message in a pop-up box. Some applications transfer total control to that message box such that the application’s main window will stop responding until you click “OK” on that message. If for some reason that box is displayed improperly – say off the screen, or behind the application’s main window – then it will appear as if the application is hung as it waits for you to click on the message you can’t see.
  • Hardware – hardware that is malfunctioning can, in some cases, cause the software that interacts with it to fail in ways that make it unresponsive. For example a USB card reader might experience a failure, and the next program to attempt to read from the device might end up “(Not Responding)” because of the problem.
  • Hardware Drivers – This is really just a combination of the previous points. All the hardware on your system is in some way controlled by software. If that software has a bug, even if the hardware is working properly, the result could be a hung application. If hangs appear to be related to interacting with a specific device it might make sense to make sure that you have the latest drivers for that device – not to mention the latest updates for Windows as well.

Viruses and Spyware – whether intentional or simply because they’re poorly written, viruses and spyware can in fact cause other programs or Windows as a whole to misbehave in various ways including causing applications to become unresponsive. Make sure your anti-virus and anti-spyware software is running and up to date.

All that is pretty vague, I know. It almost boils down to “it could be anything”, which is unfortunately fairly accurate. The actual cause, and the solution, will depend on the specifics of what you’re seeing. Does it happen all the time, or only when you do certain things? One specific application, or several? All of these things and possibly more are clues necessary to ferret out the cause and come to a solution.

Without more specifics, my general recommendation is to make sure Windows is up to date, make sure your hardware drivers are up to date, make sure that the anti-virus and anti-spyware packages on your system are working and have up to date databases. If the problems persist, try to narrow down the common causes,
if any.

29 comments on ““(Not Responding)” – What does it mean, and what do I do about it?”

    Hash: SHA1

    Because for those 60 seconds your application isn’t responding.

    Try putting a 1 second delay in a loop of 60 iterations. The performance impact
    will be negligible and Windows should be happier.


    Version: GnuPG v1.4.6 (MingW32)


  2. Hi.

    Firstly, let me thank you, for your reply.

    I followed your suggestion, but, as long as the program is in the 60 iteration for..loop, the application shows not responding in the task manager.
    I noticed one thing though, as soon as the program comes out of the loop the program returns to running state in the task manager.

    Is there any other workaround?


  3. I missed a step. Assuming this is VB6, add a call to DoEvents() in the 60×1
    loop as well.

    Not sure about VB.NET … I believe there’s something similar.

  4. Leo,

    Your article is interesting and helps me understand what might be happening, I wonder if you have missed some other scenario. Many applications are multi-threaded, and as such perform most of their long running or CPU intensive work in a thread that does not interact with the UI. In applications like this, there should be no ‘Not Responding’ scenarios. However, I do see applications that this occur even though they are multi-threaded. Is there any way that the OS is actually causing the application to not respond to the OS’s request to the application?

    In your example, you wrote the application so it was easy to determine the problem. Is there a way to determine what an unresponsive application is doing? In your case, it was network I/O, this would have caused your application to block on the OS’s low level I/O.

    Thanks for any thoughts..

  5. I’ve actually never found a reliable way for non-programmers to answer “what is
    this application waiting for” when it hangs. The developer, of course, can run
    the application in a debugger and often see exactly what;s going on, but those
    resources are not available to the average user.

    Naturally multiple threads need to interact. Typically if a UI thread hangs
    even though there’s another worker thread doing the heavy lifting, it’s because
    the UI thread is in fact waiting for something from that worker thread, or
    there’s a syncronization problem between the two. (OR there’s something in the
    UI that needs waiting for.)



  6. I’m not a PC expert, but I’m quite certain that one aspect of this problem is the speed of your broadband connection. I had a very poor download speed with one provider, and switched to BT, paying for its premium broadband service. Now I’ve got it, 20% of all the links I click on, result in ‘this program is not responding’ etc – ie an entirely sudden, new problem I never had before, and without any other changes taking place (eg software, firewall etc). So I do wonder whether my PC is now just trying too hard and too fast for its own good!!?. One thing’s for sure: it ain’t solved easily, because even BT’s own experts can’t tell me whats wrong, and how it might be put right….

  7. An update on my last comment: I SOLVED THE PROBLEM!!! I picked up a tip from another site, which was that McAfee Site Advisor is full of bugs and is prime cause of “this programe is not rsponding”… Sure enough, I disabled McAfee, and in the weeks since, I’ve had absolutely no problems – not one. So if you’ve got McAfee…..that could be your answer…

  8. hey leo and everybody here … i have a really big problem with this … please reply [email address removed]

    problem: this not responding error appears to me when im using firefox or utorrent for long time and i cant do anything (alt+f4/ctrl+shift+esc/ ctrl+alt+del doesnt help!!) then i have to shut down the laptop by pressing on the turn on/off button and this not good also this make me lose recent saved data …so please help (i use vista home premium original) and all things up to date … please reply anybody thank you

  9. I have the same problem and now cannot access anything on the computer. In looking for a fix I discovered that this is an ongoing problem since approx. 2004 on tens of thousands of computers, maybe hundreds of thousands, maybe millions, who knows. This is unbelievable. I cannot believe anyone including microsoft has not been able to or willing to fix this problem. If anyone has a fix he/she could probably make a couple million dollars.

    The issue here is that it’s not one problem. “Not Responding” is a symptom that can be caused by any of thousands of different types of problems. As a result it’s not possible to come up with a single fix for this symptom. Each problem must be fixed individually.


  10. I have “RegCure” installed on my computer but I still keep getting the Message “Not Responding” I scan with regcure but its an on going thing.
    Can You Help…….Please?

    Not at all surprised that a registry program would have no effect. This type of problem is rarely registry related. It is, however, related to the SPECIFIC program that’s not responding. There is no single, general, fix.


  11. In IE7, Tools, Internet Options, Programs, Manage Add-Ons, Find Shockwave Flash Object and disable it. It solved my (not responding) problem. Good Luck.

  12. Yes Leo, I totally agreed with you that Not Responding message in title bar is quite legal and legitimate while Windows (especially Vista) is performing lenhthy operation. However, it is indeed an overlook of Miscrosoft in designing an OS (especially a new OS like Vista and Windows 7) without thoroughly consider assigning high enough proirity interrupts to Input/Output devices such as mouse click and keyboard input.

    I have been facing the same “Not Responding” problem with Vista for about a year, and still couldn’t find any solution after so many complaints at many forum sites; e.g.;forums06

    This problem seems very likely to be Vista problem and not the broswer (IE) problem because it also happens to other application like Microsoft Excel especially when Excel is accessing the Internet to retrieve data using WebQuery. If I click a second time on any open program, I get that “Not Responding” error message almost imediately and I have to wait about 10 to 15 seconds. This is not just very frequent, but a sure occurence. It is not a Ram problem either because I have a 3G Ram in my laptop. Very frustrating indeed!
    I kind of agree with someone in a forum saying that it is a problem of Agreesiveness or Too Sensitive (timeout too fast) to this “Not Responding Issue” in Vista though Microsoft may think that it is legimate, which I think is a “Frustrating Legitimacy”! Just wonder why Microsoft is not trying hard enough to resolve this problem after so many complaints in such a long time!

  13. I too have the “not responding” curse and if I let the computer just set, it corrects itself after a few minutes. The interesting factor is that I have 2 computers. both on a cable connection, and it seems to occur more often on one than the other. I swapped the 2 machines and it happened again…more on the swapped one than the other. Ever heard on an internet connection being the culprit?

  14. Hello Leo
    I can see by the comments that tons of folk are having the not responding prob on XP, but from what i can see is that we still do not know what to do about it. so, short of reinstalling windows, what do i do about it? can you tell me?

    thanx chilly

    As you’ll see in the article you just commented on, “it could be anything”, so there’s no advice that I can give here that will simply answer “what to do about it”. It depends on all of the specifics of your situation. Reread the article and perhaps you’ll have some ideas of where to look in your situation, but this is a case where there’s little specific “how to fix” advice I can offer.


  15. I run a CADD program that exhibits the exact “Not Responding” behavior you describe while running a legitimate lengthy process. It will start the process and then give the “Not Responding” error after a varying amount of time. Unfortunately the “Not Responding” disables feedback that the program is giving to the screen in it’s own menu system. If left alone the process will finish and the program will return to normal responding state, however it is nice to be able to see the feedback that the program is giving to monitor the process. This only became a problem in Windows 7 and 8 (&8.1). The process runs and responds flawlessly in Windows XP. My understanding is that Windows pings the program and waits for a response, giving the “Not Responding” error if it decides that the program does not respond in a timely manner. My question is can the “Not Responding” ping from Windows be disabled? The processes that the CADD program runs which cause the “Not Responding” can take anywhere from a few minutes to several hours. Thanks!

  16. when I put Avast antivirus on my computer everything changed. My home page looked different at the top, everything started saying, not responding, internet explorer would freeze and say not responding, then it would come back, then it would say Microsoft is not responding, after it comes back then msn or bing is not responding, one after another. I never get to move forward on my computer. could you please give me the steps to remove this Avast antivirus from my computer.

  17. hi, is this a ram problem, almost every program whenever I click on them to select an item or perform a function, they go into not responding hibernation? some longer than others, but almost 90% of my programs.

  18. I am having trouble with all games that I play on GSN. When I finally get one to come on something pops up that says
    Retry/quit game, retry/ok or it might say quit. How can I fix this and my computer is really running slow.

  19. I get a (not responding) message off and on a lot. I live in a subdivision in a condo. I have taken my laptop to two places to fix and it works perfectly but come home and it messes up again. I had the Fiber Optics come out that I am with come out and they can’t fix either. I had another laptop before this one and thought it was the laptop, so I bought a new one, and same problem. Am I being parasite-ing off from a neighbor? The Fiber Optics company said it is not in the wiring and for me to call The Geek Squad, but they are $99.00 to walk in the door.

  20. computer deck top not responding I get a not responds recovery show I click it and go`s back to normal. I don`t know what to make of that. do you think it is bad or good!

  21. I am getting the nonresponse error message all the time. If I click on the X when the non response is happening I get a system crash. I) can I request from windows that they replace my existing windows program 2) It happens weather I am in IE or fire fox. I did uninstall fire fox and it helped some. 3) I get waves on screen all the time could that indicate a Hardware problem? 4) can the nonresponsive be caused by a slow running computer? I also have trouble when clicking on the X of getting no response.

  22. You mentioned a VB problem in your article. I’ve written a few programs that are fairly computationally intensive, and have occasionally gotten the “Not Responding” error for a few minutes. However, I’m working on a project now that has been running for approximately 12 hours displaying “Not Responding”. My question is this: is there a way to determine if the program is simply stuck on an intermediate process or if it is legitimately completing the task in an untimely manner? Some background on the situation: I’m running a machine with a Gen1 i7 eight-core and 20 GB of DDR3 RAM with the CPU priority for the program set to “High Priority”. The program is CPU-intensive, but not overly RAM-intensive. I made the rookie mistake of having it handle the entire data set at once with no intermediate checks or breaks, so the solution will need to be system-based, not program-based.

  23. When I was getting a lot of “not responding” messages, I doubled my RAM, and now it’s very rare that I get them.

  24. Frustrated!!! I ahve aol and landline, takes 7 min or longer to open welcome and when go to view messages goes to facebook but newsfeeds and cannot open messages and says I use mobile but don’t have one, WHY? Then cuts off all the time saying, sorry be patient while we restart your browser and also in the bar says not responding and facebook says I need to update my browser because not compatible with facebook? PLS HELP And with aol would firefox be better than chrome since I have windows xp and aol?

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