Will upgrading Office from 2003 to 2007 break VB programs which use Excel through the COM interop?

Question

Assume all traces of Office 2003 will be removed from the computer.

UPDATE:

I understand that I will still be able to use .xls files. I'm asking about automating Excel through the COM interop from outside Excel. When I add a reference to Excel to a VB project, it gives me a different version of the dll for different versions of Excel. If a program was compiled with a reference to Office 2003's dll, will it need to be recompiled for Office 2007? Will the code need to be updated to use the new dll?

Answer 1

It would be very surprising if there were many breaking changes between the versions. As I understand it, Microsoft has a number of customers using Office, and they wouldn't like a large number of breaking changes.

In my opinion, the above is actually a valid way of analyzing many questions of this type: "Could x possibly happen" is aproximately equivalent to "what would happen to Microsoft if they did x". If the answer is "something really bad would happen", then chances are that Microsoft figured that out ahead of time.

Of course, this doesn't work 100%. "Could Microsoft ever remove Web Application Projects from Visual Studio 2005" is a counterexample.

Answer 2

You should have no problem with your code breaking. In my past experiences, even though I referenced old versions of the Interop Assemblies, the newer version of Excel has been able to handle the calls.

Now the same can't be said for trying to use a newer version of the Interop Assemblies with an older version of Excel...