88.blacklist.zap - what is this?

Hello,

Not sure I'm posting in the right place - so please forgive and advize if I've done wrong.

I am in the UK and sending out emails from a company address to another company address. I am getting the following message:
The following recipient(s) could not be reached:

'XXXX@YYYY.com' on 21/05/2007 18:40
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<exch-svr01.XXXX.org.uk #5.5.0 smtp;550 Service unavailable; Client host [###.##.###.###] blocked using 88.blacklist.zap; Mail From IP Banned To request removal from this list please forward this message to delist@bigfish.com.>

What is this?? - I have "googled it" and people don't seem to know. Last time I sent to this recipient the same thing happened - but he still received my message. I don't want to "report" it or ask to be delisted when I don't know who the de-lister is and am worried it might be some sort of phishing (is that the right term?).. and the recipient is the sort of person I cannot directly contact (I am messaging him in my position as PA to a Director) (Director and recipient both totally non-computer literate.)

Can you shed any light on this - seems to be a big problem for a lot of people.
Huge thanks to you all,
Loopy

 

Thanks for the response. No I don't really suspect "malware" as such... actually I have no idea... was really hoping some Majorgeek afficionado might have come across this before. - As I said - it seems to be a common enough problem but no-one has a definitive answer.... it's even weirder that the messages DO actually get through - which is why I was wondering if it was some sort of an attempt to get me to reply?

 

My company is going through as well.

I did a little investigation worked and found out that the domain I was trying to email uses Frontbridge (hosted Exchange Service). I emailed the address listed in the email (delist@bigfish.com & false_positive@frontbridge.com) and they removed my IP address from their blacklist

You can get their support number from www.frontbridge.com. I emailed them as I am in Australia

 

Something just doesn't look or feel right about this. When I tried the two links, I get a Microsoft Exchanged Hosted Services page from Microsoft.