Monthly Archives: February 2018

Emails not Sending Mystery

Intermittent Email Problems are frustrating for users and can create a massive drag on productivity for your business.

A Dublin firm of consulting engineers were mystified as to why some of their emails were not sending. Users would send emails but around 40% of them would not reach their intended destination. This was beginning to be an extremely frustrating problem for everyone causing a drag on their productivity.

All users-  three Apple OS X (running Mail App) users and three Windows users (running Outlook 2016) were affected by this. This led us to believe that the root-cause was unlikely to be a mail client (Outlook, Mail App) mis-configuration issue. Most likely, the problem resided elsewhere.

We logged into their email-hosting control panel. Everything seemed fine. All mailboxes had enough space. Their MX and DNS records appeared to be in order. No anomalies  Maybe their static IP address provided by their ISP (Eir) was blacklisted? This was investigated, but their static IP was not appearing on any spam authority blacklists. After some more digging, we discovered that their email was hosted on a shared server. This is a fairly common set-up. Email hosting providers might have several clients all on the one server. The only problem with this setup is that if one or more of the entities on the server is flagged as a potential spammer, the IP address of the server gets  blacklisted. Blacklists are used by anti-spam services to block emails from “unreputable” servers. If an individual or business uses an email server which is  blacklisted, it will be very difficult to send outbound email as they get blocked by the spam-filters on the recipients side. That is exactly what was happening this customer.

The Solution

The solution was relatively simple. We migrated their email hosting from a shared server to a virtual private server (VPS). This meant they would not be sharing a server with any other entities which greatly lowered the risk of their email server getting blacklisted again.

The Follow-up

On follow-up ten days later. This frustrating email problem was solved. No more lost emails in cyberspace. No more issues with customers claiming that they never received emails. The clients had a fully functional, reliable and secure email service again.

RealClear IT are based in Dublin, Ireland. We offer  an email support service for Gmail, Outlook, Thunderbird Mail App (Mac Mail) and Office 365 remotely and on-site. Whether you’re using Eir, Virgin Media, Magnet, Vodaphone or Three – we can help. Phone us on      01 685 4833.