Cant get this to work:
Have a little mess after a Hazel misstake with 500 folders.
Is it possible to script following:
Delete all .rar files if there is a .img or .iso or .mp4 file in same folder.
(Or even better, delete all archive-filetypes if there is a diskimage-filetype or movie-filetype in same folder)
Any ideas most appriciated!

Try :
set theFolder to ((choose folder) as text)
tell application "System Events" to tell folder theFolder
set rarfiles to name of files whose name ends with ".rar"
set notRarFiles to name of files whose name ends with ".iso" or name ends with ".img" or name ends with ".mp4"
set i to 0
repeat with aName in notRarFiles
set i to i + 1
set item i of notRarFiles to text 1 thru -5 of aName
end repeat
repeat with aRarFile in rarfiles
if text 1 thru -5 of aRarFile is in notRarFiles then delete file aRarFile
end repeat
end tell
Yvan KOENIG running El Capitan 10.11.2 in French (VALLAURIS, France) samedi 16 janvier 2016 19:11:27