this issue might be related to some third-party software conflicts or corrupted Excel components. I suggest trying to check this issue by starting Excel in safe mode first.
Start the Excel program in safe mode
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1. Click Start, point to All Programs, and then point to Microsoft Office.
2. Press and hold the CTRL key, and then click Microsoft Excel.
If the problem does not occur in the safe mode, this issue might be related to some third-party add-ins in the Office program, we can try to disable them. Normally, you could do the following to disable the conflict add-ins in your Excel program:
Disable add-ins
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a. Click File menu, click Options > Add-in, click Go button in the Manage: Com-in Add.
b. Check if there are any add-ins, clear the checkbox to disable them.
c. Close the Office program and restart it.
d. Add one check back each time to the list of Add-In, restart the Office program, and repeat the above procedure. Once the issue reappears again, we can determine which add-in causes this problem and then disable it.
However, if the problem persists, please try to repair the Office programs from Add/Remove Programs (Windows XP) or Programs and Features (Windows Vista/Windows 7). Locate the Office program, right click it and choose Change. Then Repair.
If this still does not help, we can try to reinstall the Office program. To completely uninstall the program, you can also follow the steps in this Microsoft Knowledge base article to remove the Office 2007 program first:
How do I uninstall Office 2003, Office 2007 or Office 2010 suites if I cannot uninstall it from Control Panel?
http://support.microsoft.com/kb/290301 Then, try to install Office 2007 again and test the results.