Error opening Excel 2007 files


I'm not sure if it because the files are 2003 or not? When I try to open them an error message appears stating, "...the file you are trying to open is in a different format than specified by the file extension. Verify file is not corrupted and is from a trusted source..." When you select "Yes" the file will open just fine. However, I would like a way to disable the warning message. The registry "fix" for this problem: HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security
4.On the Edit menu, point to New, and then click DWORD Value.
5.Type ExtensionHardening, and then press ENTER.
6.Right-click ExtensionHardening, and then click Modify.
7.In the Value data box, type the value data, and then click OK.
* Does NOT work.
Is there another way to disable this message? I have attached a screen shot of this message.
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Do the files open on any other MSOffice implementation?  Are they .XLS files or .XLSX or .XLSM files?

I assume you're trying to open them in Excel 2007, but (a shot in the dark) you can get this error if the file was saved as part of a macro and the incorrect format was specified that doesn't match the extension.

Try renaming the extension to another (e.g., if .XLS try .XLSX.  If .XLSX try .XLS) and see if it opens correctly.

Again - a shot in the dark...

Is it possible to upload one of these files if it doesn't contain sensitive info, or you can obfuscate the data?

acmiAuthor Commented:
They are files that are being opened in 2007, but were created in 2003. I have tried changing the file extension, but we still receive the error. Also, the files will open after you click out of the message, but its more of an inconvience to continue to have to click through the messages. Especially when our users are opening so many reports everyday. I have googled and found that other people have this issue to, however the registry fix that I mentioned above does not work. Thank you in advance for your assistance.
I'll ask if other Experts have experience with this problem.  I assume you've looked at potentially reinstalling Office/confirming you have all your patches up to date?

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acmiAuthor Commented:
Yes, we have confirmed all of that. Thank you for all of your help!
Ingeborg Hawighorst (Microsoft MVP / EE MVE)Microsoft MVP ExcelCommented:
You should never, ever rename file extensions from XLS to XLSX or XLSM. The new file formats have a completely different structure. You cannot create an XLSX file by simply slapping another "X" at the end.

Is the workbook a shared workbook by any chance? You may want to try unsharing it in 2003 before you open it with 2007. Shared workbooks have all kinds of problems and are impossible to troubleshoot.

Can you save the file in 2007? Can you save it as a 2003 compatible file? Can you save it as a 2007 format file (the proper way to create a valid XLSX file).

cheers, teylyn
acmiAuthor Commented:
The workbook is not shared. I have tried saving it to the desktop in different file formats and we still continue to see the same message.
Can you upload one of these files?
Ingeborg Hawighorst (Microsoft MVP / EE MVE)Microsoft MVP ExcelCommented:
I have tried saving it to the desktop in different file formats

How did you create the different file formats? Or did you just rename the file with a different extension? The latter will not change the file format. You can call a spade a spoon, but it's still a spade.

Does the error message appear with specific files only? Or does it appear with any Excel 2003 file, i.e. files with an xls extension? If it appears for all files, have you installed the latest 2007 Service Pack? 2007 has a lot of bugs.
acmiAuthor Commented:
I've requested that this question be deleted for the following reason:

Will be removing 2007
Ingeborg Hawighorst (Microsoft MVP / EE MVE)Microsoft MVP ExcelCommented:
Please do not try to delete a question without responding to the experts. Instead of deleting the question, how about posting a comment about your plans and accepting that as the solution?
acmiAuthor Commented:
We will be removing 2007 and reinstallinig 2003. This will no longer be an issue.

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acmiAuthor Commented:
We did not use any of the solutions provided.
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