problem with pc extensions
 

Okay, files i'm trying to open a .DAT file and a .PRO file, now i know that the .DAT file could be anything but does anyone know a hex editor that can open a 500mb .DAT without problems?
And does anyone here know what a .PRO file would come from or what program I can open it with?

i'm unsure about a file size limitation on UltraEdit, but I'd give it a shot

it's the best hex editor i've found

.pro Prolog source code file
Graphics profile file (DOS)

source:
http://www.webopedia.com/quick_ref/fileextensionsp.asp

Well I don't know about a hex editor, but a ".pro" extention could be one of two things. One a Graphics profile file, or two a Prolog source code file.

thanks, i'll give it a try