Community Tip - Did you know you can set a signature that will be added to all your posts? Set it here! X
Having looked into it myself. it can't be done. You need to pay for the full version to have it removed.
Or you do not use Prime 6 or 7, but 5 or 4, which for Express makes no functional difference. In those versions the 'watermark' is just in the footer.
Success!Luc
