APPLE INSIDER
If Photoshop seems to be fighting you at every turn, and you keep getting told that it “could not complete your request because of a program error,” here’s how to fix some common problems to help get it running smoothly again.
Maybe it happened suddenly after an update, or perhaps it’s been happening for a while now. You go to open a file in Photoshop, but instead, the program spits out an error that reads, “Photoshop could not complete your request because of a program error.” If this sounds familiar, don’t worry — you’re hardly alone. As it turns out, plenty of users have noticed this problem cropping up in recent years.One of the most frustrating parts of this error is that it is entirely nondescript, and doesn’t really tell the user anything. As it turns out, it can be caused by one —- or more — of several problems.
Source: APPLE INSIDER