im having the same problem and its reall weird because it used to work, i run wpi from the cd, and ive tried to change so many things, and something that works when i test it locally doesnt work when i create the iso, its frustrating, it would work perfectly if it wasnt for %wpipath% somehow changing the %cdrom% variable to match it, so before "set wpipath=%cdrom%" %cdrom% = E: after it %cdrom% = E:\ so i tried taking the extra \ from the config.js and it went even stranger, its been doing my head in for the last 2 days, lol, i need %cdrom% to just = E: because i use it for switching cd's E:\ wont work for this purpose, and for some reason it changed what drive is the cd, lol, ive commented out the cmdow so i can see whats happening. for echo Found CD-Rom as drive %CDROM% REM Determine the WPI startup path. REM if wpi should run off the cd the replace %~dp0 with %cdrom%. set wpipath=%cdrom% REM Hide this command window. REM %wpipath%\Tools\cmdow.exe @ /hid REM Special registry tweak needed. regedit /s "%wpipath%\wpi\common\wpi.reg echo %wpipath%\wpi\common\wpi.reg REM Make WPI directory the current directory. for /f "delims=: tokens=1" %%i in ("%wpipath%") do %%i: cd "%wpipath%" i get.. Found CD-Rom as drive E: E:\wpi\common\wpi.reg E:\ but when it tried to install i get "Windows can not find D:\Install\trillian-v3.1.exe..." so its also changes which letter is the CD-Rom for some reason o_O i also had to change the path in config.js to cmd1[pn]=['%CDROM%Install\\trillian-v3.1.exe /VERYSILENT'] Otherwise it tried to install to D:\\Install my cd path looks like E:\WPI\ E:\Install\ why does %cdrom% change to imitate %wpipath% it would probably work fine if the 2 variables kept themselves to themselves the annoying thing is it was working until a couple of days ago, and i cant work out what ive messed up