can't add open with list

I had a problem.  I was trying to add StataMP.exe as a default program for a certain file type.  However, in the choose-which-program-to-open-this-file-with dialog, when I clicked browse and selected Stata11MP.exe, it was not added to the list of options.  As an experiment I tried adding vlc.exe, and it was added.  Thus I looked for a difference.
A quick search in the registry for the name of an application that I could choose
HKEY_CLASSES_ROOT\Applications\StataMP.exe\shell\Open\command
with a default value of
"C\Program Files\Stata11MP\Stata11Mp.exe" "%1"

---> E:\Stata11MP\Stata11Mp.exe" "%1"