As I remember, on WinXP was necessary to make registry change to allow it. Here is a problem description: http://support.microsoft.com/kb/896054
Registry: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions] "MaxAllowedZone"=dword:00000001 -- <http://forum.pspad.com/read.php?2,60966,60971> PSPad freeware editor http://www.pspad.com
