Most of us have experienced the problem of trying to receive an e-mail with an attachment that was too large for our mail system to accept, or trying to deliver a large attachment to someone with the same limitations. We recently conducted a survey of corporate e-mail users in order to determine the impact of attachments on e-mail systems. Here’s what we found:

• A mean of 29% of e-mails contain attachments. However, more than one-half of the e-mails for 9% of users contain attachments.

• Of the 29% of e-mails that contains attachments, 19% of these attachments exceed 5 megabytes, while 6% exceed 10 megabytes. (Note that these are the percentages of e-mail that contains attachments, not the percentages of all e-mail.)

• However, 7% of users cannot receive e-mails larger than 5 megabytes, while 30% cannot receive e-mails larger than 10 megabytes. Only 4% of users have no limit on the size of e-mails they can receive.

Because e-mail has become the de facto file transport mechanism in most organizations, and because attachments are getting larger over time, attachment management is becoming a more serious problem. Add to this the fact that numerous Osterman Research surveys have shown that growth in messaging-related storage is the most serious problem faced by e-mail administrators. The problem will become only more serious as unified communications (Compare Unified Communications products) and unified messaging systems become the norm.

One solution to the problem is to employ an attachment management system that will strip attachments from e-mails upon their receipt, replace them with a link in the body of the e-mail, and store the attachment in a separate repository; users simply click on the link to retrieve the attachment. The advantages, other than not hitting e-mail size limits as noted above, are better e-mail server performance and reduced storage requirements because only a single instance of an attachment is stored.

If you’d like a copy of our research results, you can download it with our compliments.

Michael Osterman is principal analyst of Osterman Research.