ProcessStartInfo("C:\Program Files\Adobe\Reader 11.0\Reader\AcroRd32.exe")
uses double quotes to make VB aware of a string between them. They are working fine.
When VB passes that string to the OS, it removes the double quotes (they are just for programming in VB anyway). That makes the string appear as several strings separated by spaces:
C:\Program
, then
Files\Adobe\Reader
and
11.0\Reader\AcroRd32.exe
. That's not what a process expects to see.
Try this one
ProcessStartInfo("""C:\Program Files\Adobe\Reader 11.0\Reader\AcroRd32.exe""")
The outermost double quotes remain. But inside the string, there are two doubled double quotes, which VB translates into two double quotes that remain in the string when it's passed to the OS.