I'm not 100% sure what your exact issue may be, but a few extra things to check:
- File format of original files (are they all the same)
- Color profile of originals
- Folder and file permissions (I have had issues with some files having limited permissions and interrupting actions because PS couldn't save them)
Personally, I also try to only batch 50-75 files ata time (even if I have a few hundred to do). Just to make sure no errors are coming up, and so PS doesn't getting too bogged down with the batch/memory hog.
They're all JPEG, all coming from the same source (Images coming off of a Kodak PS410 scanner). I've also checked to see if they're 'read only' but they aren't. Odd thing is, I've taken this same set of photos to another computer and ran the same action and everything ran fine. As far as memory goes, I don't think that should be an issue as I'm set up with 16gb of RAM. And as far as what I was recently working on, these folders had probably 40 images max in them.
I'll be running another batch on another set of images (coming from a different source) today and see what happens, if anything.
Which of the usual trouble-shooting routines have you performed so far?
This should not be an issue, but just to make sure: Do the file- or folder-names contain any no-no-s like slashes?
Another thing: Are you scanning as jpgs and oversaving them after editing? Because that would seem like a sub-optimal workflow with regard to image quality.