Invalid Class String message

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Invalid Class String message

Anonymous

My operating system is Vista Ultimate 64 Bit. With my Canon digital camera I got software containing a programme called ZoomBrowser EX. Each time I try to run this program a get a 'Critical Error' message saying 'Invalid Class String'. What is the cause of this and how do I fix it? I have contacted Canon but they tell me that it is a Microsoft problem.

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Answer 1

Hi Bev-stan,

Thank you for posting on the forum.

Quick questions, have you tried uninstalling the program and reinstalling it again? Do you have any programs running in the background of Vista when you did your install? What I can suggest that you try is to uninstall your program > use the Windows Installer CleanUp Utility > Perform a Clean Boot of Vista > then reinstall your software.

Here’s a couple of link to articles that could be of help fixing your problem.

Description of the Windows Installer CleanUp Utility

http://support.microsoft.com/default.aspx/kb/290301

How to troubleshoot a problem by performing a clean boot in Windows Vista

http://support.microsoft.com/kb/929135

For your future reference, please be advised of Microsoft’s

THIRD PARTY SOFTWARE DISCLAIMER

Using Third Party Software, including hardware drivers can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee that any problems resulting from the use of Third Party Software can be solved. Using Third Party Software is at your own risk.

Hope that helps, please post back and let us know if that worked for you.

JohnD

Microsoft Answers Support Engineer

Visit our Microsoft Answers Feedback Forum and let us know what you think.

Answer 2

One solution that works: reinstall the Canon software from the original CD. I just added ZoomBrowser EX (great program!) and other Canon software to my new Surface Pro 4 (using an external DVD drive via the USB). Surface Pro 4 uses uses Windows 10. Could not get ZBex to work by just copying the existing files from my Windows 10 desktop (via USB memory stick), as that gave the "invalid string error". The W10 desktop had the ZBex software on it from previous Windows 7 setup, and there were no problems when I upgraded to W10. The ZBex software works fine on my W10 desktop and my wife's Windows 7 desktop. I tried but failed to find a download site for the Canon software to go straight onto the new Pro4, hence the resort to CD (luckily I could find it). But at least it is a surefire and easy install solution that works. Good luck! Hugh

Answer 3

Anonymous

I do have problem on Skype work befre now not

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Answer 4

I have the same problem on Windows 8. I have been using Zoom Browser for many years. I have my computer set for automatic updates. Since the last automatic update I cannot start Zoom Browser. When I try to start it a box pops up that says"Critical Error" In the box the message is "Invalid Class String"

Answer 5

Got the same problem with Windows 7 64 and I'm sure my machine is Super Clean. Could it be an MSXML problem or some "process" thats not starting properly. Don't know if it's connected but I cannot "double click" a *.docx shortcut - Word returns a "There was a Problem sending the command to word" Error. My file associations are registered correctly

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Invalid Class String message

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