Yesterday I tried to subscribe to Expactica.com for about 30 minutes, and gave up considering the website a major failure.
They claim to be directed to the highly-educated expatriated people living in many european countries, but fail in small details without a single line of explanation.
As an example, I've tried to use a special mailbox so I can filter them out of my mainstream email. This allows me to receive emails from them and cancel the mailbox whenever I cancel the subscription (hence preventing the delivery of new unsolicited emails on my mailbox).
The procedure is simple, and is part of the RFC5321 (IETF.org's Simple Mail Transfer Protocol specification) and in RFC5322 (IETF.org's Internet Message Format specification).
Obviously, no highly educated expatriated person working abroad in the IT industry as a software engineer ever tried to use this, or they all failed, because the system just don't accept that you subscribe or message Expactica.com withour a "proper" email address (meaning "one we can guarantee that'll be available to spam afterwards").
So far, Expactica.com sucks.
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