Today I downloaded
and "successfully" installed the Async CTP 3.0 on an XP PC (x86) with VS 10 Professional SP1.
I did not have async ctp installed before.
Now Async CTP 3.0 is not listed in the "Add or Remove Programs" panel.
AsyncCtpLibrary_Phone.dll is not installed <<<<<<<<<<<<<<<<
I wrote a blog post that explained some likely causes (and fixes) for this problem: