It's a standalone program and doesn't require installation.Nice, simple program to use. This program decoded e-mails saved from my old computer, including attachments. I did have to save the messages into an intermediate file before dragging them into my current version of OE.
That's a great little program.Here's a freeware .dbx reader I found. And a comment in one of the reviews.
OE Viewer
http://www.snapfiles.com/reviews/OE_Reader/dbxviewer.html
It's a standalone program and doesn't require installation.
This is a nifty little freebie! I think I'll keep it. Hope it helps you.