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Jeremy, Computer Repairer
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I cannot open itunes, it keeps telling me there is a webtoolsbox.dll

Customer Question

I cannot open itunes, it keeps telling me there is a webtoolsbox.dll file missing. I have tried to reinstall but it won't let me, keeps saying I already have an installation already going on. The same thing happens if I try to uninstall itunes. I also cannot install any windows updates and I think the two things may be related? I have registry booster/cleaner software but it tells me it has fixed all registry problems but it does not solve the problem of itunes or the windows updates. Please can you help?
Submitted: 5 years ago.
Category: Computer
Expert:  John T. F. replied 5 years ago.
Hello! My name is XXXXX XXXXX self-employed tech, and I'm offering my time in good faith today to provide advice and information.

Restart your computer.

Go to the Control Panel and click "Add/Remove Programs" to uninstall iTunes and related software components in the following order and then restart your computer again:

Apple Software Update
Apple Mobile Device Support
Apple Application Support

If you have trouble uninstalling any of the above, try the following Microsoft Fix It utility to troubleshoot the uninstallation:

Once you've completed the removal, restart your computer and re-install iTunes again. Make sure you download the latest release:

If you *still* receive errors when attempting to install/uninstall or sync after installation, try temporarily disabling any anti-virus or firewall software you may be running.

Let me know how this works for you. If you run into additional issues, you may need to correct those system issues before this Question can be resolved.
Customer: replied 5 years ago.
I had previously tried all of the above, and none of them worked. To be sure I did it again and followed your instructions to the latter but again every time I try to install itunes it comes up with an error window that I already have another installation application in process and I cannot proceed? Closing down the firewall and anti-virus software does not correct the problem either.

Expert:  John T. F. replied 5 years ago.
To clarify, you have attempted to use the Fix It utility?

Customer: replied 5 years ago.
Yes I tried the Fix It Utility, it finds the problem with the windows updates and says it has fixed it, but when I try to do the windows updates they still fail.
Expert:  John T. F. replied 5 years ago.
Okay, as you have a more system-intensive issue not directly related to iTunes, I am going to move this to a more suitable category (it landed under Mac) and opt out so that an Expert more familiar with the internals of XP can assist you.

Please do not reply back to this thread until another Expert picks it up or it may delay the process.

Thanks and good luck!
Customer: replied 5 years ago.
Thank you very much. Will wait to hear from you.
Customer: replied 5 years ago.
If I try to either download itunes again (ie. reinstall it over the old one) OR if I try to uninstall the existing one, I get an error message that says "Another installation is in progress. You must complete that installation before continuing with this one." If I try to install the windows updates,it simply tells me on the windows update screen that the following updates were not available ... currently there are 29 updates that will not install.
Customer: replied 5 years ago.
For further information. If I try and open the existing itunes I have installed on my computer (the version I was trying to uninstall in the hope it would fix things!), it comes up with an error message that says "this application has failed to start because MediaToolbox.dll was not found. Re-installing the application may fix this problem". I click OK and then another error message comes up that says "itunes was not installed correctly, Please re-install itunes. Error 7 (Windows error 126)."
Customer: replied 5 years ago.
Hello - do you have any answers for me yet please?
Expert:  Jeremy replied 5 years ago.
Hi my name is Jeremy I would liek to help you with your Itunes issue.

Try this

Hold the windows key (looks like a flag on the keyboard) and press R

type services.msc in the runbox and push enter

Double click "Windows Installer"

In the Properties dialog, change Startup type to “Disabled”, click OK, and reboot your computer. This stops the service. After your computer reboots, again open Computer Management (right-click on Computer and select Manage), open Windows Installer Properties, and change the Startup type back to Manual.

Try to uninstall and re-install itunes once more

Let me know if that makes a difference.


Customer: replied 5 years ago.
Hi Jeremy

This afternoon, I managed to uninstall itunes and other associated apple software (apply updater etc) by using the MSConfig utility (similar to the way you describe above), however I still get the error message about the coreFoundation.dll missing file associated with AppleSyncNotifier.exe when I start the computer. I tried to reinstall itunes but it told me it was unable to reinstall as I had missing components on my computer? I noticed I still have mobileme and safari on my computer but no matter how I try, including your method outlined above, I cannot uninstall these two programs. It either tells me there is another installation in progress or if I disable start up using your method above, it tells me I cannot access those programmes to uninstall. I feel the problems are all related to this missing CoreFoundation.dll file. If I could find a way to get this back, and put it in the right place? It may solve the issues?? What do you think, any further ideas?
Expert:  Jeremy replied 5 years ago.
Hi I sure do have some more ideas :)

Download Revo Uninstaller

Try to uninstall using this, let me know if this completely removes it if not I have more steps :)
Customer: replied 5 years ago.
mmmm.. well, I did as you said and I was still unable to uninstall the programmes just by chosing the uninstall option..still tells me that I have another installation process going on! In fact, it does this with pretty much any programme I have tried to uninstall (not just apple stuff). Anyway, after failing to install using the simple progress, you get the option to 'scan' and then it comes up with all the files and they can be deleted to remove the programme from the computer, so I was able to do this. However, having now removed those programmes I thought was affecting this AVCoreFoundation.dll, I am no further forward as I still get the error message about AppleSyncNotifier when I restart the computer, I am unable to install itunes and probably more importantly, I cannot do the windows update I mentioned in my original e-mail. It fails every time.
Expert:  Jeremy replied 5 years ago.
Try this go to Start / Programs / Accessories click command prompt


reboot after the scan and try to re-install once more
Customer: replied 5 years ago.
i did as you say and shortly after the scan started an error message appears which says:

"Files that are required for windows to run properly must be copied to the DLL Cache.

Insert your windows XP Professional Service Pack 3 CD now."

I don't have an XP CD as it came pre-installed on the computer?

What next?
Expert:  Jeremy replied 5 years ago.
Visit Click Install Framework 4.


Can you try one more uninstall utility for me.


Download and install this clean up utility.

It will create a program called the windows installer clean up utility on the start menu.

From the list remove Bonjour, Mobileme, Itunes, Quicktime, or anything apple related (some may be already gone but this is a double check)

Restart the computer.

Try to install Itunes once more.

If no luck Go to Start / Control Panel / User Accounts

Create a new Windows XP User account that is an administrator

Click Start / Log off, log on to the newly created account and try the Itunes install once more.

Let me know if we have any luck with these :)

Customer: replied 5 years ago.
OK, so I managed to do the first part (Install Framework 4).. that worked.

I then tried to install the clean up utility from softpedia, but that wouldn't install (usual story about already having installation in progress).

I believe I had already managed to get rid of all Apple related software using the previous uninstall download you suggested.

Tried again to do the windows updates..still no joy.

Then created new Administrator Account. I had partial success with this in that I was actually able to install itunes, however when I went to run the programme, it came up with an error message that Apple Application Support was not found and this is required to run itunes.

I tried windows updates from that alternative administrator account but again they all failed to update.

I restarted computer and this time I get two error messages; the first as always is the one about AppleSyncNotifier.exe and that the CoreFoundationAV.dll file is missing and now I get this second error message about the Apple Application Support file that is missing?
Expert:  Jeremy replied 5 years ago.
1/2 way there :)

I may have a work around,

Download WinRAR and install from


1. Right-click the iTunesSetup.exe icon and choose "Open with WinRAR".
2. Once the EXE is opened in WinRAR, double-click AppleApplicationSupport.msi and when the installer window is open choose "Repair".

Keep me updated :)
Customer: replied 5 years ago.
OK - probably have taken a slightly backwards step. I tried to do as you suggested but when I right clicked on the itunes icon there was no option to 'open with WinRar'. I thought perhaps I needed to go to the set up.exe file in itunes, so tried that and found I could open with WinRar, however upon doing so, the option to 'repair' wasn't immediately available. When I did eventually do something where I could see repair, I tried it but the result that itunes wouldn't open was the same.

I thought then I would try to do the above in the alternative administrator account, however I couldn't locate the itunes.exe file in explorer that would allow me to 'open with WinWar', so I tried to reinstall itunes with google chrome. During the process, it seems to have uninstalled itunes and now, I cannot reinstall itunes again!! Argghhh!

I tried to go back to the start of the process, even deleting the administrator account I set up and establishing another one, but no matter which account I try to install itunes into, I get the following message:

"the installer encountered errors before itunes could be configured. Errors occurred during installation. Your system has not been modified. Please run the installation again or finish to exit."

So am kind of back to square one. I keep trying to install windows updates but the following will not update:
Security Update for Microsoft .NET Framework 4 on XP, Server 2003, Vista, Windows 7, Server 2008 x86 (KB2572078)
Security Update for Windows XP Media Center Edition 2005 Update Rollup 2 X86 Edition (KB2502898)
Update for Microsoft Office Outlook 2007 Junk Email Filter (KB2596560)
Security Update for Microsoft .NET Framework 4 on Windows XP, Windows Server 2003, Windows Vista, Windows 7, Windows Server 2008 x86 (KB2478663)
Microsoft Office File Validation Add-in
Security Update for Microsoft Office PowerPoint 2007 (KB2535818)
Security Update for Microsoft Office 2007 System (KB2553089)
Security Update for Microsoft Office Excel 2007 (KB2553073)
Security Update for Microsoft Visual C++ 2008 Service Pack 1 Redistributable Package (KB2538243)
Update for Microsoft Office 2007 System (KB2539530)
Security Update for Microsoft .NET Framework 2.0 SP2 on Windows Server 2003 and Windows XP x86 (KB2572073)
Security Update for Microsoft Office 2007 System (KB2553090)
Security Update for Microsoft .NET Framework 2.0 SP2 on Windows Server 2003 and Windows XP x86 (KB2539631)

I feel that all the problems I am experiencing is related to some windows configuration, if we could get to the route of that problem, then maybe the itunes would install? The error message about CoreFoundationAV.dll still appears as well when I restart the computer.

Expert:  Jeremy replied 5 years ago.
I did a little research looks like the CoreFoundation is part of MobileMe you could download and re-install it from this link

Also visit

You may have a point with the updates not installing see if the above fixes windows update. You may want to check your clock in the corner, also make sure your date/time/timezone are all correct, windows update will give you trouble doing anything with the wrong time/date
Customer: replied 5 years ago.
Still having major problems trying to get anything installed - always get the error message that I have another installation in progress! Very frustrating! Any further ideas on how I could force through an installation? Then I can try and download MobileMe
Expert:  Jeremy replied 5 years ago.
Go to start, run, type services.msc.

Double click Windows installer and press stop, you may need to try to press start as well try to install with it first stopped then started

Customer: replied 5 years ago.
Start and Stop options are greyed out... ie. I cannot select either of them?
Expert:  Jeremy replied 5 years ago.
Try this

Select what version of XP you are running, Pro,Media Center, or the regular SP3, download the correct .zip file

Open this and run the .reg file in the zip press yes to make changes to the registry. I think something is messed up with your default services.

Then try the uninstaller after you reboot.
Customer: replied 5 years ago.
OK - Tried that and it didn't make any difference. I have had a good look about on the computer and all evidence of apple products have been removed to the best of my knowledge. Still get the CoreFoundationAV.dll error when I restart, still can't download itunes as get the configuration error, can't install MobileMe as it still tells me I have an installation in progress, still can't update windows and the Start and Stop options in Windows Installer is still greyed out. So no further forward unfortunately? Is there any way of restoring the default settings in my XP Media Centre to try and resolve any problems there? What can I try next?
Expert:  Jeremy replied 5 years ago.
I can open this question to see if anyone might have a fresh idea to get a second opinion, let me see if any other experts have any ideas.

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