[Exim] Microsoft Exchange

Hi all,

I'am using linux on my desktop and have to relay my mails via an M$
Exchange server. In my exim.conf my smarthost is:
smarthost:
driver = domainlist
transport = remote_smtp
route_list = "* my.exchange.de bydns_a"

main.log tells me:

host my.exchange.de [123.456.789.098]: 550 Relaying is prohibited

Is there another transport option to an exchange server!

Thx in advance!

--
Never make anything simple and efficient when a way can be found to
make it complex and wonderful ;-)
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