Thanks, it helps a bit.

It seems to work for the text I want to add, but the problem is that the body property doesn't seem to give the RTF contents of the mailitem. If I append RTF to the Body, my added text is not formatted, but displayed as rtf code, and the already existing body lost it's formatting.

I do something like this:

item.Body = item.Body & strAdres

where strAdres is the formatted text (in this case rtf).
The original formatting is lost, and the added text is not formatted, but displayed as rtf code.

If I do it like this:

item.Body = strAdres

the text is properly formatted, but obvious the original message is gone.

So i need to find a way to read the original rtf contents of the message, so i can alter it.