In 2014 Wirtualna Polska acquired O2, thereby increasing their total market share from 28.5% to almost 43% and significantly strengthening their place as the number one ISP and email provider in Poland. WP (Wirtualna Polska) operates at least 11 million active mailboxes.
The Polish email provider market is divided up between WP, Gmail (second place), Grupa Onet (third place), Allegro (fourth place), Interia (fifth place), and Gazetta (sixth place).
Here are some more details about WP that might be helpful to senders:
Anti-spam: WP has a home-built anti-spam system and is comprised of five analyses:
Prioritized delivery: WP uses the Return Path Certified whitelist. They also have a trusted-safe sender program aimed at protecting their users against phishing. It’s DKIM based. Senders on in the program have an icon placed by their mail in the UI that lets users know the mail has been verified. According to WP, the first partners to receive Trusted-Safe Sender Certification were Allegro, Alior Bank, and PayPal.
Managing complaints: Because WP takes the number of spam complaints generated as the main indicator of spam (every complaint is verified by a WP admin), it is vital to keep complaints to a minimum.
List acquisition & sign-up: Senders should always use confirmed opt-in and should never use auto opt-in and addresses should not be obtained from a third party. Ideally, your registration form should leave the, ‘I would like to receive newsletters and/or email offers’ box unchecked.
Unsubscribe: Return Path recommends providing list-unsubscribed headers for all emails sent to Wirtualna Polska. The specified URL should either use the mailto: scheme or be an HTTP URL that unsubscribes the user with a single click without any further confirmations required.
Engagement: WP considers complaints to be an excellent indicator of the relevance of a sender’s mails they consider this when making decisions to block or throttle or eventually block.
Connection and throughput: From WP’s Postmaster: “If you get error message like “421 Too many concurrent connections from your IP,” please change the configuration of your mailserver to not more than 40 concurrent connections and a max throughput of 90 messages.
Block removal: If you’re blocked consult the bounce codes that WP sends. Complaints are the most common reason for a block but failure to authenticate correctly could also cause a block. WP uses SPF and DKIM. SPF is must if you want to deliver to WP.
Reputation: WP has their own reputation database and shares data globally thanks to DCC. Since WP also uses the Return Path whitelist, checking your global reputation score via the Return Path’s Senderscore.org is a good idea.
Sending-infrastructure requirements: WP uses DKIM and SPF. Senders should comply with RFC standards relevant to email. You can read more about their requirements in English here.