Sheffield Hallam University blocking Plusnet mail?

[#1]

Never had a problem emailing a friend at Sheffield Hallam University (*@shu.ac.uk) until today, when I have twice received the following rejection message:

Quote

554:Your access to this mail system has been rejected due to the sending MTA's (84.93.230.235) poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means. This message was created automatically by mail delivery software on the server avasout07.

I'm assuming the Plusnet server has been blacklisted for some reason - any ideas as to what can be done about it please?

[#2]

Only one list that I can see http://www.mxtoolbox.com/SuperTool.aspx?action=blacklist%3a84.93.230.235

[#3]

Last time it was Trend Micro doing it

[#4]

Thanks guys - it's only about a 10 minute walk from Plusnet Towers to the main SHU campus - it's a lovely day here so perhaps someone from PN fancies a stroll down there to ask their IT department why they have suddenly decided to be so beastly!   

[#5]

Wash you mouth out with soap 
Walking 
They might use the Plusnet bicycles though http://community.plus.net/blog/2012/07/13/plusnet-staff-take-part-in-new-and-improved-cycling-progra...

[#6]

Anyone familiar with the current state of Sheffield's roads would probably feel much safer walking! 

[#7]

Just had an exchange of emails with my friend at SHU so the block appears to have been removed.
Thanks if anyone at PN was involved (a Usain Bolt or Bradley Wiggins wannabee I suspect.)   

[#8]

Nothing done here as far as I'm aware. The error looks like it's an RBL that Sheffield Hallam are using that refused the mail rather than anything we were doing this side though.

Quote from: Oldjim

Last time it was Trend Micro doing it

I've checked all of our IPs against their lookup tool and none of them are listed.

[#9]

Thanks Bob! 
Glad it got sorted quickly by whatever means because the email was quite important, although you have to be a bit suspicious about a piece of kit that blocks your attempted email, and at the same time advises that if you think the block was applied in error that your best course of action is to, in effect, ring or text the intended recipient!