Can't change margins

Here's the scenario:

I have an ERD I made that is on an ANSI-D Sized sheet. I
saved the drawing and went back into it and now the margins
for the left side are reading something like 1000+ for left
and bottom. I cannot change the margins at all as they keep
defaulting back to those numbers.

The printer in question is an Oce 9400 and I was printing
ERDs from it yesterday.

It's Visio 2002 SR-1 on a fully patched XP Pro box.