"open in external editor" not working

I use "open in external editor" a lot to edit pictures in Photoshop, but it has stopped working. Now it launches Photoshop, but doesn't open/load the relevant image.
What has changed since I had this working?
I had a couple of kernel panics, and used "archive and install" to re-install Tiger, and then 10.4.3.
I am using iphoto 5.0.4 and Photoshop CS 8.
Any remedies/help gratefully received.


Hi Nige,
It is a Photoshop problem and probably because it is missing files.
this is an old copy/paste from MacFixit it.
Try this suggestion I copied and pasted from MacFixIt first
"Photoshop CS: Fix for file opening problem Yesterday we reported that since installing Mac OS X 10.4, Photoshop CS refuses to open any new files or create any new documents, reporting a "program error" when one tries to do so. Our previously reported workaround involved re-installing Photoshop CS, but MacFixIt reader Bryan Schappel now offers a faster solution:
"This happens because the Archive and Install option does not copy over a necessary folder for Photoshop. The critical folder is called 'ScriptingAdditions' and is stored in the main Library folder. This folder contains one file 'Adobe Unit Types' that makes Photoshop open files that have been double-clicked or dragged to the PS icon in the Dock.
"Simply move this folder (and file) from the 'Previous System' backup to the Library folder, relaunch Photoshop and all is well again. No need to completely re-install.""
I copied an pasted instead of putting the link in because it is not on the front page and you would have to search around to find it. Hope it is ok to do that here. If you don't still have the folder then you have to reinstall PhotoShop.