I had Office 2010 starter and Outlook 2010 installed. I recently purchased the Office 2013 click to run version (paid monthly subscription) and installed Office 2013. After installing 2013 I noticed that when I opened up Excel files they would still open in Office 2010. I uninstalled Office Starter 2010 and uninstalled Outlook 2010.
I then manually fixed the file associations for Word, PowerPoint, Publisher and such, however I could not manually fix the Excel file association.
Excel documents show the correct icon however when I double click on them the following error appears "This action is only valid for products that are currently installed."
I have used the Office 2013 repair process, I have uninstalled and reinstalled Office 2013, I have manually uninstalled office 2013 using KB 2739501 (http://support.microsoft.com/kb/2739501/en-us ) and I still can not open Excel documents.
Recently I found that I can not do mail merges either using Excel documents as the data source and I believe the two items are related.
Any suggestions?