Q. I have two versions of the same program installed and I need to use the older version to open the files. Iâ€™ve tried to set the default in the Finder but it always seems to open the newer version.
A. While you can select a file in the Finder and choose â€œGet Infoâ€. Then set the default application to open a file, your Mac may open the wrong applications that you have double-clicked. In the pre-Mac OS X days, your Macintosh would open the legacy file based on the â€œCreatorâ€ code in the Resource fork, which was used to store file resources such as a finder icon or image preview. Mac OS X has done away with the Resource Fork for compatibility reasons.
Without the applicationâ€™s â€œcreatorâ€ code, your Mac may have no idea what program should open the file. Like Windows and Unix systems, the Finder now uses the â€œdot file extensionâ€ in the file name to determine the file:application relationship. The Finder stores this information in itâ€™s â€œcom.apple.LaunchServices.plistâ€ file. If you cannot set the default application, this â€œplistâ€ may be corrupt. To fix it, Trash the file and the Finder will create a new one with the default relationships. However some applications such as those from Adobe, Microsoft and Quark will always tend open with the highest installed version. So dragging and dropping on the dock icon or choosing â€œOpen Withâ€ from the contextual menu may be only way to control the behavior.