I have compiled a 32-bit Excel Add-in and it worked fine in our previous environment (Windows XP x64, Excel 2007 32-bit)
It also works fine with Excel 2010 32-bit and Windows 7 x64, I just had to register the project DLL with the regsvr32 command, and I could use the Excel add-in on a computer that did not have Matlab installer (only the MCR library)
However, once we transitioned to Excel 2010 x64, the add-in did not work anymore.
I tried re-registering the DLL and it didn't work.
I got the error 429, "ActiveX component can't create object"
This is the same error I got with Excel 2010 32-bit, and it was fixed by registring "myproject.dll" with the "regsvr32" command.
However the fix did not work for Excel 2010 x64.
Does this mean I need to recompile the add-in using a 64-bit version of Matlab (and Matlab Compiler/Builder)?
Or is there an easy fix to this problem?