Emails Bouncing

HI

I am having a few issues sending emails to clients,this dsnt happen with every email so finding it hard to find a fault at my end. So I guess I am posting on here to make sure the issue is at the other end.

I have an exchange server 2003 email is sent via my isp's smtp server.

When an email is sent I get the following info in the message that bounces back

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"Wed 2010-09-15 11:44:00: A-record resolution of [smtp.dslgb.com] in progress Wed 2010-09-15 11:44:00: Host [smtp.dslgb.com] resolved to [195.92.193.207] Wed 2010-09-15 11:44:00: Host [smtp.dslgb.com] resolved to [195.92.193.221] Wed 2010-09-15 11:44:00: Host [smtp.dslgb.com] resolved to [195.92.195.234] Wed 2010-09-15 11:44:00: Host [smtp.dslgb.com] resolved to [195.92.195.233] Wed 2010-09-15 11:44:00: Attempting TCP connection to [195.92.193.207 : 25] Wed 2010-09-15 11:44:00: Socket connection established (10.221.1.21 : 46631 -> 195.92.193.207 : 25) Wed 2010-09-15 11:44:00: Waiting for protocol initiation... Wed 2010-09-15 11:44:00: <-- 220 mailrelaym2.core.theplanet.net ESMTP Exim 4.43 Wed, 15 Sep 2010 10:44:00 +0000 Wed 2010-09-15 11:44:00: --> EHLO procare-ltd.co.uk Wed 2010-09-15 11:44:00: <-- 250-mailrelaym2.core.theplanet.net Hello host-87-75-153-123.dslgb.com [87.75.153.123] Wed 2010-09-15 11:44:00: <-- 250-SIZE 26214400 Wed 2010-09-15 11:44:00: <-- 250-PIPELINING Wed 2010-09-15 11:44:00: <-- 250 HELP Wed 2010-09-15 11:44:00: --> MAIL From:<AdamBalmer@procare-ltd.co.uk> SIZE=2441 Wed 2010-09-15 11:44:00: <-- 250 OK Wed 2010-09-15 11:44:00: --> RCPT To:<jackie.hope@fusion21.co.uk> Wed 2010-09-15 11:44:11: <-- 550-Callout verification failed: Wed 2010-09-15 11:44:11: <-- 550-550 5.7.1 :127.0.0.5:Client host 195.92.193.207 blocked using Wed 2010-09-15 11:44:11: <-- 550-88.blocklist.zap; Mail from IP banned. To request removal from this list Wed 2010-09-15 11:44:11: <-- 550 please forward this message to delist.forefront@messaging.microsoft.com " 

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