Use regedit and find: HKEY_CURRENT_USER\Software\Adobe\MediaBrowser\MRU\Photoshop\ FileList
Caution. Make a back up of your registry if you edit it, make sure ps is closed when/if you do. Screwing up the registry can really screw things up so if you don’t know what you are doing in terms of backup, DON’T.
I’ve tried what you suggest, however, the "open recent" list remains when I open Photoshop, even after a reboot. I checked the registry and the HKEY_CURRENT_USER\Software\Adobe\MediaBrowser\MRU\Photoshop\ FileList is empty. It must be coming from somewhere else.
set the list length to 0 in the prefrences, then open a couple of files, then exit and restart ps?
Then the only thing I can suggest is to download and run AdAware SE Personal (free). One of its features is to clear the MRU for any or all applications.
It’s typically used to remove spyware, but if you have it check for "negligible risks", it will list the MRU for all of your applications and you can optionally delete them.
edit: Or Dave’s suggestion <grin>
A lot depends really on your reasons for wanting to clear the list.
It might be because you open files over a network (not recommended!) and PS is taking a long time to register these on start up. If so, setting the list to Zero won’t help because Photoshop looks for the last 30 files regardless.
Your reasons might even be that you don’t want other users to know which files you have been working on. Again setting to Zero is pointless because resetting it to 30 will simply show them again even after closing and reopening the program.
For either scenario I would suggest you create 30 very small jpegs then write an action which opens and then closes them again. This will effectively replace the 30 files in the list with your 30 "dummies". You could probably even script photoshop to run the action as soon as you start the program.
Hope this helps.
Chris.