Hi Friedrich,

That was useful reading but I am still stuck. I have been fiddling around with this with not much success.

What I think I want to add is entries which when exported to a reg file look like:

Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.csv\OpenWithList]
[HKEY_CLASSES_ROOT\.csv\OpenWithList\TransPost.exe]
[HKEY_CLASSES_ROOT\.txt\OpenWithList]
[HKEY_CLASSES_ROOT\.txt\OpenWithList\TransPost.exe]
[HKEY_CLASSES_ROOT\Applications\TransPost.exe]
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\Frien dlyAppName]
@="\"TransPost\""
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\shell]
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\shell \open]
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\shell \open\command]
@="\"C:\\Program Files (x86)\\Cadro\\TransPost\\TransPost.exe\" \"%1\""
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\Suppo rtedTypes]
".csv"=""
".txt"=""

and importing that gives me the following script lines:
::Registry Key "HKCR\.csv" (Always Install)
::Registry Key "HKCR\.csv\OpenWithList" (Always Install)
::Registry Key "HKCR\.csv\OpenWithList\TransPost.exe" (Always Install)
::Registry Key "HKCR\.txt" (Always Install)
::Registry Key "HKCR\.txt\OpenWithList" (Always Install)
::Registry Key "HKCR\.txt\OpenWithList\TransPost.exe" (Always Install)
::Registry Key "HKCR\Applications" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe\FriendlyAppNa me" (Always Install)
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\FriendlyAppName\( Default)" = "TransPost" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe\shell" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe\shell\open" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe\shell\open\comman d" (Always Install)
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\shell\open\comman d\(Default)" = "C:\Program Files (x86)\Cadro\TransPost\TransPost.exe" "%1" (Always Install)
::Registry Key "HKCR\Applications\TransPost.exe\SupportedType s" (Always Install)
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\SupportedTypes\.c sv" = (Always Install)
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\SupportedTypes\.t xt" = (Always Install)

so I edit duplicating % and putting "" after =
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\shell\open\comman d\(Default)" = "C:\Program Files (x86)\Cadro\TransPost\TransPost.exe" "%%1" (Always Install)

::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\SupportedTypes\.c sv" = "" (Always Install)
::Registry Value (REG_SZ) "HKCR\Applications\TransPost.exe\SupportedTypes\.t xt" = "" (Always Install)

It now compiles but only installs these entries:
[HKEY_CLASSES_ROOT\Applications\TransPost.exe]
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\Frien dlyAppName]
@="\"TransPost\""
[HKEY_CLASSES_ROOT\Applications\TransPost.exe\Suppo rtedTypes]
".csv"=""
".txt"=""[/SIZE]

Any suggestions would be greatly appreciated.

Julia