Apparently Caro.net has gone out of business. According to two posters on WHT they got the following email earlier this week.
"U_nfortunately the company is closing. We have made arrangements at the last minute to have another company come pickup the servers and they will attempt to install them in their network. They are going to use the same IP addresses and hopefully the servers will be back online some time tomorrow._
Caronet Engineered Hosting
Technical Support Team"
I used to run into the Caro.net guys at HostingCons back in the day. I thought they were respectable dudes. Either I was wrong or there is some part of the story I am missing. I hope I am wrong because if they left their customers high and dry and gave them basically zero notice to the reality the owners knew was coming likely months in advance, they are without a conscience.
Regardless, a big surprise to see them gone.