disk overflow in XY4

[Bill Troop bill@xxxxxxxx]

I'm trying to edit a 5MB file in XY4 -- a Eudora mailbox
actually. I have 18 MB free on the drive but XY 4 gives
me a disk overflow message. (1) Is there any way out
of this kind of seemingly fatal crash? (2) Is there some
way to avoid it and still edit such a large file? Sorry to
appear so ignorant but it's a long, long time since I
edited large files in XyWrite.