1.4.9 Guidelines for sending e-mail attachments

Modern computers can create and handle huge files, and the use of graphics and photo images boosts file size dramatically. This can cause problems when files are sent as e-mail attachments, especially for recipients with slow dial-up access.

Here are some guidelines for sending e-mail attachments:

1. Be aware of the size of the files you are sending. In Microsoft Windows  you can check these details in ‘Windows Explorer’ or ‘My Computer’.
2. As a very arbitrary guide, think twice before distributing files bigger than 1Mb via e-mail. For people who use a dial-up connection to collect their e-mail, an attachment of this size can take between five and ten minutes to download.
3. If a document is less than a page and consists of text where formatting is not overly important, copy it into the body of the e-mail message rather than sending it as an attachment. An MS Word document attachment containing only one word is about the same size as 3000 words of e-mail text. This will also reduce recipients’ concerns about the virus risks associated with email attachments.
4. Only send very large attachments (over 1Mb) by previous arrangement with the intended recipient(s).
5. Consider using WinZip (or some equivalent) to compress large files before sending them. This can reduce the size of files by up to 80%, but make sure the recipient(s) can handle that format.
6. If you have large files to make available to a number of people, consider placing them on one of the Cochrane File Transfer Protocol (FTP) servers; then you need only send people the details of the file name and how to access the server. The UK FTP server, for example, has an ‘Uploads’ directory that can be used for this purpose (ftp://ftp.cochrane.co.uk/uploads). As well as dedicated FTP programs, web browsers such as Netscape and Internet Explorer can be used to send and retrieve such files.