Venezuela’s biggest and most important ISP, CANTV, was my first serious email provider, since it is tied to my ADSL connection, and I previously used several different dial-up providers (T-Net, IFX Networks) with no specific interest in email. CANTV mail service used to be provided with the highest standards of quality in the country, particularly as per malware and UCE control, and general abuse surveillance. Hey, even one of the former insider guys is quite known inside our FOSS community!

I’ve previously (1, 2) blogged about the huge problems CANTV is facing with their mail service. They don’t answer, and sometimes even bounce, mails to abuse or postmaster, and temporarily suspended or degraded their abuse statistics web site. All in all, they are providing a poor customer service and are being listed in several blacklists all around the world.

Sometimes I get warnings from mailing lists since their border MTAs are refusing to deliver messages to the mailboxes. So if you sent me my signed PGP public key, please forgive my ISP for probably bouncing your message. I thought I could live with this problem, since it’s probably temporary, but today a friend from El Salvador told me that all of his mail to cantv.net addresses is bouncing with this message.

Diagnostic-Code: smtp; 550 5.7.1 <...>... Mail from
168.243.89.79 refused: Vea http://abuso.cantv.net/bl/dul.html

So after taking a look at the whois record for that block, and doing a lookup on the reverse entry for 168.243.89.79, I think that a proper conclusion would be Venezuela’s biggest ISP is currently blocking most mail from El Salvador. And probably other countries. Terrible news. And please use my at debian.org mail address if you need to get in touch.