Plain text messages: original text included with paragraph markings?

[ryanlink]

This is bizarre and likely some kind of corruption, but I'm trying to
avoid reinstalling outlook:

A client was messing around with his Outlook 2003 signature and
"include original text" settings. Now replies to plain text messages
appear completely blank, no signature OR original text. That is, until
you type one character. Then the sig and original text appear, WITH
PARAGRAPH MARKINGS (and the dots where spaces should be). If I click
the show/hide formatting button, the signature and original text
disappear.\

Replies to HTML messages work as designed.

He's using Word as his email editor. If I disable that, the problem
goes away, but he wants to use Word. I've tried enabling and disabling
all markings in a blank new message, switching to indented replies,
turning off include original text, all to no avail. Any ideas?

 

[ryanlink]

Update: I have tried renaming and deleting Normal.dot, didn't work.

The problem also occurs if I compose a new message in default HTML and
switch to plain text. Everything disappears until I hit a key, then
reappears with formatting marks. If I click Show/Hide, everything I
typed BEFORE switching to plain text disappears, including the
signature. Anything I typed after switching to plain text is still
there.