Wednesday, May 12, 2010

Microsoft's Click-to-Run and Office Automation

Today's lesson: When Office is installed using Click-to-Run, it doesn't support automation.

We use Excel automation via C# in our application, and when testing against the new versions of Office we hit a bump in the road. Office Home and Business 2010 typically installs via Click-to-Run, which is designed to have a small footprint, and as such does not register itself for programmatic automation.

So when you hear this sound: "Retrieving the COM class factory for component with CLSID {00024500-0000-0000-C000-000000000046} failed due to the following error: 80040154" even though Excel is apparently installed, you probably have this issue.

More here about Excel automation and the expected registry keys.

It is suggested that there will be an alternative MSI-based installer that presumably will not have this problem.