I've never been able to get regular internet activation to work - with Office 2007 and now with Office 2010. I've always had to use the telephone activation, which is rather annoying.
I finally stumbled across a solution that worked for me.
You'll need close down any running office applications, and run this command (I used cxrun
)
<full_path_for_your_installation>/c:/windows/system32/cscript.exe "C:\Program Files\Microsoft Office\Office14\OSPP.VBS /inpkey:<your_key_here>
Then open up any office application and follow the activation prompts. This time it should work instead of giving you the "An unspecified error has occured 0xC002001C" error.