Problem timed out from messagelabs.com

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    cluster2a.eu.messagelabs.com[85.158.139.103]:25: Connection timed out

    cluster2a.eu.messagelabs.com[85.158.139.103]:25: Connection timed out

    mail163.messagelabs.com[216.82.251.38]:25: Connection timed out

I checked my IP in Symantec blocklist "http://ipremoval.sms.symantec.com/lookup/",

but does not have a negative reputation.

How can this problem be resolved?