directory/file permission problems

[kilroy]

I'm having a problem with this new webserver I've moved to. plesk is running fine and all, but when I go through the file manager, and chmod this .txt file to 600 so only the owner can read and write it, I assumed the apache server/plesk user would have owner privis! Yet when I try to load the page, and open and read the txt file, the kick out function I added simply, well.. kicks out with, 'cannot open', when I change the chmod to 660, or 666, then the file opens fine.

Any ideas if I've set up something on the server wrong?

A thousand thanx!

Kilroy