I'm having the same problem.
I tried installing Visio 2007 and Project Professional 2007 (after paying
for the downloads).
I had previously installed Office Professional Plus 2007 Beta, and then the
B2TR for Office.
After getting the Error 2711, I uninstalled all the Office Beta products,
deleted the registry data and cleared my Temp folder.
Now, I cannot even install Office Professional Plus (Beta 2 - NOT B2TR),
nevermind Visio and Project 2007.
Does anyone have a resolution for this?
Thanks,
--Sam