@oneless, yes, it's supposed to be 'REM'. %PF% variable is used to transform "C:\Program files" onto "C:\Progra~1". @oneless, winamp is supposed to register its extensions during setup. btw just change the extension REG ADD "HKLM\SOFTWARE\Classes\.ogg" /VE /D "Winamp.File" /F REG ADD "HKLM\SOFTWARE\Classes\.wav" /VE /D "Winamp.File" /F REG ADD "HKLM\SOFTWARE\Classes\.mp3" /VE /D "Winamp.File" /F REG ADD "HKLM\SOFTWARE\Classes\.???" /VE /D "Winamp.File" /F