Should be getting better now.
The server that the Coin/Stamp sites are on is ours only, not shared with anyone. The mail server is shared. One of the people we share with had something compromised (likely a poorly coded contact form) on their site that allowed the spammers access and they went in and queued a half million emails to be sent. This does several bad things....
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Obviously it jams up the resources on the mail server and slows everything down for quite sometime. Computers are fast but a half million is a BIG number.
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It slows down posting tremendously because the software interacts with the mail server upon posting to send subscriptions.
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It just about immediately puts our mail server on several spam blacklists.
I got us off the last blacklist last night, but it can take up to 24 hours for the refreshed list to filter down to all the caches. We've hopefully adjusted things so that even if it happens again it will not slow down posting.
IMPORTANT: None of your information was compromised.
Nothing here on this site was compromised. The mail server was just compromised in a way that allowed them to send spam to their own email lists.