   Registry
  hii add in registry userSpace :HCU/Environment/myVar = "d:\bin";then i add myVar to path (in registry)(path = %path%;%myVar%)but echo %path% writes : "C:\Program Files\Microsoft Visual Studio\Common\Tools\WinNT;%myVar%"  !!!!!!Why %myVar% is not "d:\bin" ? thanks 
  Because it''s not a system/environment variable. RTFM. ;  what is a system/environment variable ?how to make a system/environment variable ? ;RTFM(s). ;  I would like to make it permanent, not volatile (just for a process), i think, SetEnvironmentVariable is just for the process !  ;User Environment VariablesIt appears that your application can not modify user environment variables; to do that you need to use the WriteEnvironmentStrings action in an MSI installer.Your lack of initiative, however, is shocking. ;  You are exempted idiotic comments! ;quote:Original post by encom  You are exempted idiotic comments!You aren''t. Given several pointers to information from Microsoft''s MSDN database, that you failed to search (or at least indicate that you''ve searched) suggests a "spoonfed" mentality which is detrimental to a developer. Finding things out on your own (rather than running to a forum and asking breathless, panicky questions at first frustration) is a core part of becoming a competent developer. The failure to realize and abide by this will result in curiosities like "developing" your own game engine but having no idea how to make a game from it (with apologies to Promit).So, RTFM. 