Only three out of four emails made it to their intended recipient in the second half of 2011, down for the first time from four out of five, which was typical over the last three years, according to a new study released by deliverability firm Return Path.
ISPs are getting tougher on filtering and blocking email. They are using more stringent reputation metrics to determine whether email should be passed on to recipients. Metrics include engagement data and subscriber complaints.
More:
http://www.thecmosite.com/author.asp?section_id=1137&doc_id=241094
Reversing the trend of increasing inbox rates from the first half of 2011, North American (NOAM) inbox rates experienced significant declines with an 8% drop, bringing in inbox placement rates closer to 79%. Spam folder placement jumped 19% to 7.4% in the second half, and missing, or blocked email, increased a whopping 38% (13.3% missing rate) during the same time frame.
In Europe, Middle East and Africa (EMEA), for the second half of 2011, 15% of email never reached the inbox, with 5% being identified as spam and 10% being blocked by the ISP. EMEA showed the greatest improvement in inbox placement rates compared with rest of world at 85% of email reaching its intended recipient.
Despite showing gains in the second half of 2011, Central and Latin American (CALA) commercial email still struggles to make to the inbox with almost 30% of all email being blocked or classified as spam. CALA had only 71% of emails delivered to the inbox, and the highest amount of email sent to the spam folder worldwide with 18% of all permission email being banished to the spam folder. Additionally, CALA senders saw an average of 10% of opt-in commercial emails being blocked. Central and Latin America still lags the rest of the work in its inbox placement rates, coming in only second to the Asia-Pacific (APAC) region.
See also:
Virus Bulletin, probably best known for its VB100 antivirus test award, also periodically tests commercial spam filters. Its March 2012 report is out (summary; PDF report for subscribers), and the news isn’t good. Most commercial spam filters caught significantly less spam this time around than in other recent tests. The false positive rate’s up, too.
http://www.infoworld.com/t/anti-spam/report-spam-filters-are-getting-worse-189250
and:
Due to the complexity of accurately detecting and filtering out spam, on rare occasions a legitimate email from a friendly source may be blocked from reaching your Inbox. This is called a false-positive. If you feel that a legitimate email message was inadvertently filtered, you may want to ask your friend to send a follow up email to verify the issue exists before contacting support. If you notice that multiple email messages are being delayed, bounced, or not delivered, please contact iCloud Support directly.
http://support.apple.com/kb/HT4899
