Emailing Attachments

As well as text, email quickly evolved into a way of sending all sorts of files across the web easily

One of the best features of e-mail is that you can attach other documents and files to your messages. This remains a very useful way of transfering files between people, ensuring it's delivered securely to the person you intended to receive it. There are a few pitfalls to avoid, though.

File Formats

While you can send almost any file along with an email, that doesn't mean you should. Avoid using odd file formats, or expecting that the receiver will install a program just to read/access your document.

Common file formats you can send

.jpg or .jpeg: Photos and images

.pdf: Adobe Acrobat Documents

.docx: Word Documents

.zip: Compressed/bundled collection of files. Better than attaching 20 separate files.

Formats to avoid

.bmp: Uncompressed image format - makes large files. Convert it to a jpg before sending.

.exe: program file - often used to make viruses, so many e-mail programs will block it

.unknown: If you don't recognise the format, don't send it or open on that you receive. Could be dangerous.

File Sizes

Most people have a limit on both the size of individual messages they can receive (adding together the sizes of all the attachments with a message), along with the total size of their message inbox. Therefore, they won't appreciate you sending them huge messages often.

If you've got a collection of files or photos, consider uploading them to a common network location or somewhere online. You can also use a free service to send huge files such as Be aware that, once uploaded, anyone with the link they provide will be able to download the file.


Remember that your message may not just be seen by the person you send it to. It could be forwarded on, or you may make a typo when typing their email address and it goes to the wrong person. Assume that anything you send may be sent to and seen by anyone.

To do this in Microsoft Office, go to File>Info then Protect Document then Encrypt with Password. Just remember that there is no way to recover this password if you lose it!

Send the password separately to them, using something other than email. e.g. by Whatsapp. That means that if their email gets hacked, the person won't be able to find the password to open the file.