c# - Windows default shell and path not found -

i've changed windows default shell application , everythings ok. aplication in c# , need run external python scripts, , here error because path variable not found.

i've tried set path started process :

  process.startinfo.environmentvariables["path"] = "c:\\python27;c:\\python27\\scripts"; 

this dosen't work.

the problem path variable not loaded because i've changed default windows shell explorer.exe dosent come up.

thank you.