This is not an issue with ALM/QC, it is a microsoft issue.
Occurs often enough to be mentioned in Microsoft Technet Blog. Link Below.
The solution is to create a registry entry refering to the correct install directory for Excel.
In my case had to use res://C:Program Files (x86)Microsoft OfficeOffice12EXCEL.EXE/3000 since running W7x64 with Office 32bit.
![alt text][1]
After the change, you will need to reboot your PC.
[Click HERE for The Microsoft Excel Support Team Blog posting.][2]
[1]: /storage/temp/37-microsoft+office+export+to+excel+missing.jpg
[2]: http://blogs.technet.com/b/the_microsoft_excel_support_team_blog/archive/2012/06/06/export-to-microsoft-excel-from-internet-explorer-9-does-not-enter-the-url-in-the-excel-web-query-dialog.aspx