Reply Mail as spam classified in WM

[Randy]

I sent a reply mail from a friend and short after that I got a reply mail
with following content:

This message was created automatically by mail delivery software (Exim).

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

(e-mail address removed)

SMTP error from remote mailer after end of data:
host mx0.gmx.net [213.165.64.100]: 551 5.2.3 Your mail shows indications
of viruses or spam. We cannot accept your mail. {mx089

I am not able to reply mails with or without attachments
Whats going wrong?
Any ideas??
Thanks

 

[Dave]

you (actually your email server) might be on a blacklist....

http://www.emailtools.co.uk/tips/blacklists.htm

http://www.mxtoolbox.com/blacklists.aspx

 

[Gary VanderMolen]

From your headers, it appears you have Avast configured to scan
outgoing messages. This could be part of your problem.
Antivirus programs should never be used to scan messages, either
incoming or outgoing. For more on this see
http://www.oehelp.com/OETips.aspx#3

By the way, your IP address 91.11.81.16 is on at least one blacklist:
http://www.spamhaus.org/pbl/query/PBL112754

Gary VanderMolen