Interesting. No clues here.
I can go to Tools, Options, and run down
a list till I find fonts & sizes that affect the
words in the body of the message.
~ jan
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Yes I have font settings but no setting concerning a
message's actual formart other than HTML and Plain Text.
I have it set to plain text.

What "sizes that affect" the formatting of your posts? What
NR are you using?

I'm using Agent Forte to read newsgroups.
The font size in Agent doesn't mangle my
posts for me... I was just brainstorming
that it could be a possibility for you.
~ jan
(Using short sentences & hard returns.)
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Zone 7a, SE Washington State
Ponds: www.jjspond.us