Order of the file types in file type list
To find a match, Trados Studio searches this list starting at the top, and working its way downwards. It processes a file as the first file type which matches. It is for this reason that, when you create a file type, the SDL software puts the new file type at the top of the list.
You can change the order of file types in the list, but be aware that the order of the file types in the list is important. You can have more than one file type with the same file name extension. For example, you can have many XML file types. In such cases you need rules that identify the file type by the file's contents. In such a case, put the generic XML file type (which has no file content rules) below the other XML file types named *.xml. If you do not do this, the SDL software will assign any XML file to the generic XML file type without even examining the file contents.