A quarter of legitimate marketing emails still fail to make it to users’ inboxes, according to research by software supplier Lyris Technologies. The study also found that the proportion of permission-based emails delivered to junk mail folders by European internet service providers (ISPs) has shot up to 20.4 per cent, compared to 7.6 per cent last quarter.

According to Stefan Pollard, director of consulting services at hosted software provider Email Labs, email deliverability in the second quarter of this year was affected by the introduction of Sender Policy Framework (SPF) checks to ISPs’ spam filtering systems. These checks are designed to ensure that emails purporting to be from a particular domain actually come from the domain’s list of approved senders.

‘This is the first time we’ve seen SPF checks start to creep into content filter tests,’ says Pollard. ‘The good news is that it’s an easy fix for marketers – in fact, it’s completely in the sender’s power to make sure the [SPF authentification records] are accurate at all times.’

The research from Lyris also found that while image spam is decreasing, spam using PDF, PowerPoint and Excel files is on the rise.

Dave Dabbah, vice-president of marketing for Lyris, comments: ‘It’s important for marketers to keep track of spam trends, because as spammers change the way they attack, the ISPs change the way they monitor and filter email messages. PDFs and other files may have been safe a year ago, but today they’ll attract a higher spam score.’

Lyris’ study monitored the delivery of 436,558 permission-based email messages from a variety of organisations sent to multiple accounts at 58 ISP domains in the US, Canada, Europe and Australia.

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