Can't add a reference to microsoft.office.interop.excel

Question

I am running Visual Studio 2010, .NET 4.5, and Office 2010. I get a warning on some legacy code that I am trying to run that I am missing an assembly reference for Microsoft.Office.Interop.Excel==12.0.0.0 and Microsoft.Office.Interop.Access==12.0.0.0.

After searching, I was able to find this post

I installed the Primary Interop Assemblies, they show up in my control panel when I go to Add/remove programs. However, I still do not have a selectable reference to the interop assemblies from the add reference dropdown for COM or .NET addins in Visual Studio. I also do not have the interop assemblies when I navigate to C: > Windows > assembly > GAC, as was suggested in the previous post.

Searching my system for anything labeled '.Interop' does not yield the Office.Interop files. Really frustrating, because it says that the assemblies are installed.

Adding a simple reference to Microsoft.Excel and Microsoft.Access COM addins does not remove the warnings.

UPDATE: I was able to get this working. Version 12.0 of the Interop Assemblies is native to Office 2007. I was running Office 2010 which has version 14.0 of the assemblies. The assemblies are backwards compatible, but I was unable to 'see' them in the browser because I had to select my project to build on 'Any CPU' instead of just 'x86'.

Is your target framework correct in your project properties? — Sam, Nov 26 '13 at 13:17
@terrybozzio Don't see Microsoft.Office.Interop anything in any of the folder in that path — Dobbes, Nov 27 '13 at 04:28
Yes, you have to "Browse" for the Project. Also, you have to know where they are ... Not too hard, but also not at all obvious. You could also add your solution above as an answer to your question here. — RBarryYoung, Dec 03 '13 at 14:01

score 4 · Accepted Answer · answered Dec 03 '13 at 14:24

I was able to get this working. Version 12.0 of the Interop Assemblies is native to Office 2007. I was running Office 2010 which has version 14.0 of the assemblies. The assemblies are backwards compatible, but I was unable to 'see' them in the browser because I had to select my project to build on 'Any CPU' instead of just 'x86'.

score 2 · Answer 2 · answered Apr 14 '14 at 10:36

You need to select 'Microsoft Office Developers Tools' when installing visual studio. See http://msdn.microsoft.com/en-us/library/54ds2za4%28v=vs.100%29.aspx

Btw, if you get 'A selected drive is no longer valid' message when changing vs setup, uninstall sp1 first.

score 1 · Answer 3 · answered Jun 30 '16 at 23:35

I had this happen when going back to a very old version of Office (went from 360 to 2000)... I had to download the PIA redistributables from here: https://www.microsoft.com/en-us/download/details.aspx?id=3508

Then I had extract the .msi file that the "PIARedist.exe" file created. I used 7-zip for that. (Running the .msi installer didn't work for some reason. Not quite sure why...) I removed the reference to "Microsoft.Office.Interop.Excel", and then I added/browsed for "EXCELPIA.DLL" which I had extracted from the .msi file. This seemed to resolve the issue I had.

Can't add a reference to microsoft.office.interop.excel

3 Answers3