Why does CheckSUR take a long time to run?

I've been asked a lot recently about the CheckSUR utility that our engineers send to customers to assist with servicing corruption issues.  I typically ask that all of our engineers run this tool regardless of the "ease" of the potential fix and the utility gives us a lot of information about the state of the serviving stack when issues are present.  Additionally, the tool was built around specific scenarios that we know we can fix, so this can and does resolve a lot of servicing issues just by running it.

The main question we get though is why does it take so long to run?  I've heard any number of reasons but wanted to give the limiting factors when it comes to running the tool.  The main thing is the spindle speed of the disk on the system you are running the tool on.  This is because the CheckSUR utility comes as a packaged payload.  We create the \Windows\CheckSUR directory on your system and then unpackage the contents of the utlity to your local drive before we ever run the actual tool.  This takes up the majority of the time (~75-80%).  The rest of the time is used for running the tool and generating the log file.  If you have a large amount of corruption on the system, such as a failed service pack, then it may take a little longer but in general the tool should be usable in about 15mins from the time the installer starts.

If you need to run the utility again on the system, you should be able to just re-run the utility you've downloaded (assuming you kept it) and it will be much quicker because it doesnt need to rebuild the directories for the \Windows\CheckSUR directory and can just run the tool.  All of the log files for the utility are held in the \Windows\Logs\CBS\CheckSUR.log file.  We will recreate this file each time the utility is run so the only the most current entries will be in the log.

If you were unaware of the utility or would like more information on it, please see the following: http://support.microsoft.com/kb/947821


Comments (25)
  1. @Tim, probably because the process is locked, you could find and delete the process to stop it if you wanted to do that but I would leave it alone.  Seeing as its been a while, did this ever complete normally?

  2. CheckSUR rarely has taken more than 15mins and I've run it literally hundreds of times with customers.  I'd be interested to know what your output looks like if its taking 1.5hrs.

  3. @Jack, if you want to share your CBS logs I can take a look and see what might be causing the problem.

  4. Anonymous says:

    "15 mins?"  Who are you kidding??  CheckSUR actually runs for about two HOURS, with no indication of what it is doing, or how long it will take, or whether it is stuck, or even what its actual purpose is.

    This is TERRIBLE human factors engineering — so typical for Microsoft!  Come on, Microsoft, do you really want millions of people to spend an extra $1000 each to buy Apple computers, just to avoid Microsoft's miserable software quality?  No?  Well, then, WHY does Microsoft abuse its customers like this??

    BTW, I can be reached at:  http://www.burtonsys.com/email

  5. Drew,

    Do you mean as an enterprise wide solution?  Just trying to understand why you would want to use FirstLogon?


  6. Well part of the problem with that solution is that CheckSUR doesnt run as a standalone tool once its installed.  You have to download it each time you want to use it, but the second running of the tool will take less time because the payloads will already be installed on the system.

    Hope that makes sense.

  7. @James,

    If its taking that long either you have a lot of corruption in servicing (or on your disk) or you have a different type of problem.  I'd be interested to know the outcome unless you've decided to go with another operating system.

  8. Anonymous says:

    While running CheckSUR this evening, I also encountered the long wait with the CheckSUR progress bar not moving for a long period of time.

    Whenever I have processes that appear to be hanging, I fire up good ole Process Explorer from the Sysinternals Suite to see if I can determine what is happening.

    You can find Process Explorer on the Microsoft Technet Site here:


    Upon looking at the CheckSur Log located at C:WindowsLogsCBSCheckSUR.log, it was apparent that CheckSUR was Checking Component Store.

    I started up Process Explorer and found the CheckSUR.exe process and was able to watch as CheckSUR accessed each of the Component Keys in the Windows Registry.

    So, it was obvious that CheckSUR was working, slowly but surely.

    Eventually CheckSUR did complete and added the following to the end of the CheckSUR.log file:


    Seconds executed: 1970

    No errors detected

  9. anony.muos says:

    I think CheckSUR’s description on the Download Center pages is confusing (I think MS just copy-pasted the description from Windows Update where it is appropriate as Windows Update actually scans computers and then offers fixes). The download center description should say "Use this tool to fix a *potential* inconsistency which *may have developed* in the Windows servicing store which may prevent the successful installation of future updates, service packs, and software." It says "an inconsistency *was* found" which confused me when I first read it. Then again, the design of the NT6 servicing stack needs to be changed in the future to entirely eliminate corruption, slowless, taking up so much disk space and have the ability to slipstream back.

  10. Drewfus says:

    "We create the WindowsCheckSUR directory on your system and then unpackage the contents of the utlity to your local drive before we ever run the actual tool.  This takes up the majority of the time (~75-80%)."

    Perhaps it is a good candidate for FirstLogonCommands?

  11. Drewfus says:

    Yes, as an enterprise solution:

    1. To save time (as per this post)

    2. So it is just there if needed (as though it were an inbox tool)

    Hopefully this can be done without issue.

  12. Drewfus says:

    Not really!

    Each time i run 'start /wait wusa.exe Windows6.0-KB947821-v11-x86.msu /quiet /norestart' i get three new processes – checksur.exe, checksurlauncher.exe, CheckSURPackage.EXE. CheckSUR.log gets updated after several minutes, and info is appended to CheckSUR.persist.log. No errors reported.

    Also, if i firstly delete C:WindowsCheckSurv1.0*  the extraction time only seems to add around a minute, but the total checksur.exe time is ~10 minutes.

  13. Cobalt says:

    Great, now that means another hour and a half of waiting and misery.

  14. pankaj says:

    Its true.. its taking so much time..!! Keep Running and No idea.. What it is doing? (At least there should be some screen Like other installer where we would be knowing where we are?).

    I Passed approx 30mins and till now its running..

  15. james says:

    I'm an hour in and still waiting! Good opportunity to browse for an alternate OS!

  16. Jeff25 says:

    I'm finding the same … CheckSUR runs for at least 1.5 hours.

  17. tom says:

    I am dealing with a corrupted Vista 64 bit SP2 installation that would NOT upgrade to Windows 7 Ultimate 64 bit. I found CheckSUR and began running it approximately 3 hours ago. CheckSUR has been taking about 4 to 10 percent of my quad-core processor and has been utilizing the hard disk at about 20 Mbps for the entire 3 hours.  I have no idea how much longer it may take. The "Installing" status bar moved to 50 percent within 3 minutes, and has been frozen there for the last 3 hours.

  18. TechieTone says:

    15 minutes my ***!  I have (been FORCED to) run CheckSUR on several occasions on several different hardware configurations (various clients).  Not ONCE has it taken less than an hour to run–usually WELL over, even if it finds no errors.  It is disturbing that such a tool is even needed.  Short of hardware component failures causing corruption, how can the operating system allow itself to get to a state where it cannot install updates to itself.  Ridiculous.

  19. DocHayward says:

    Chiming in, I'm getting an 800B0100 error on one of my windows updates.  CheckSUR ran for about 20 minutes, then stopped and gave me an installation complete message, with a close button.  Ok – so I hit close and … nothing happens.  

    Well, what did the process do?  It gave me no information.  I look in my All Programs list, no mention of "System Update Readiness Tool".  Tried searching for CheckSUR, no file exists.  

    Windows Update does list that I installed a "Hotfix for Windows".  I tried again to install the update that wouldn't work, but it can't.  Error 800B0100.  Fantastic.

  20. DocHayward says:

    Oh-ho!  I found the CheckSUR log, finally, because I found its file location online here:


    Odd that Windows search function could not locate the file.  Now that I found the log, it tells me the process ran for 18.73 minutes – much better than 1.5 hours!  It also tells me I have 14 errors: 6 PSI Payload Files missing, 4 CBS MUM corruptions, and 4 CBS Catalog corruptions.

    And it tells me nothing about how to fix this.  Fantastic.  Now I know I have errors.  What do I do about them?  

  21. Finch Computers says:

    Just cleared a large number of viruses from a customer's computer. Afterwards I found that it couldn't check for MS updates so I downloaded this hotfix. Had to do it twice, as the first time it didn't run. Second time it got to 80% complete, then did nothing for a long time. I assumed that it had frozen due to Vista corruption so I cancelled!!! Now from seeing this cvonversation I realize that I should have just let it run. Thanks Microsoft. A little message saying what the tool is, what it is doing and that it may take a long time would have really helped! Is that so difficult for Microsoft employees?

  22. ali says:

    I have to say Microsoft no longer  care about their customers 15 minutes is a joke and as said by a lot of other people not knowing how much longer it will take is the worst bit

  23. Jack says:

    VSS / Windows Update problems for 2 months now. I GUESS I'LL HAVE TO DO A COMPLETE OS REINSTALL, NO OTHER OPTIONS seem to be available. OS is OK except it won't update. Missing file, but WHAT FILE? Who knows, it isn't logged in event system. Can't install latest version of system update readiness tool, fails but doesn't say why. What crap is this, anyway? Oh, I forgot this is MS BS!

  24. Tim says:

    It's been at 80% now in the Installing Updates state for around 25minutes.

    Why does pressing the Stop Installation button not stop it?!

Comments are closed.

Skip to main content