I started getting the same message/error

I started getting the same message/errors yesterday. Today, I tried uninstalling and re-installing PowerPivot. Now, I am unable to re-install. I get an error message that says "Setup is missing prerequisites: This add-in requires Excel 2010. If you have 32-bit Excel, you must install the 32-bit version of the add-in. If not, you must install the 64-bit version. This add-in requires that the Office Shared Features Component of Microsoft Office 2010 is installed. Go to http://go.microsoft.com/fwlink/?LinkId=168472" which takes me to a Microsoft page: http://www.microsoft.com/downloads/details.aspx?FamilyID=ceb4346f-657f-4d28-83f5-aae0c5c83d52&displaylang=en which is the following page: Microsoft® SQL Server® 2008 R2 Feature Pack I have verified that I am running 32bit Excel 2010, and verified that the Office Shared Features components are installed. No luck - I get the same error message each time. Any suggestions? I've uninstalled PowerPivot and now I can't get it back.