Font style change while writing email - from HTML to Plain text - How?

[David Smithz]

Hi there,

Occasionally when writing an email in Outlook 2003, I find that it just
changes the email to plain text.

Lets say for example I have half written the email, and I am looking through
it to review it, before my eyes it just changes as if I had selected the
plain text option from the Format menu. But I had not actually done this.

Does anyone know why this could be happening? Very bizarre behaviour that
would seem like a virus or something, but I'm all up to date in that aspect.

Thanks in advance

David.