Add new Path to the path variable in Registry

[newtoclarion]

Hello All

I am trying to add a new path to "Path environment variable". (actually I want to add the path regardless the method)

my code retrieved the path correctly but it fails to update the path, even I tried to create a new variable in the registry but also failed.

Reg_pth1                 CSTRING(255)
Reg_pth                  CSTRING(255)

code
 Reg_pth = GETREG(REG_LOCAL_MACHINE,'SYSTEM\CurrentControlSet\Control\Session Manager\Environment','path')
 Reg_pth1 = Reg_pth & ';c:\00'
 if PUTREG(REG_LOCAL_MACHINE,'SYSTEM\CurrentControlSet\Control\Session Manager\Environment','path',Reg_pth1)
    stop('not added')
 end

Best Regards