BOOT CAMP 157 (11/01/01)

Email file attachments

File attachments are at the same time one of the most useful and most infuriating features of email. They add enormously to the functionality of sending messages over the Internet but they increase upload and download times, adding to the cost of Internet use, and they can open the door to destructive viruses.

Newcomers to the Internet and email sometimes find it difficult to grasp the concept of file attachments, and in the past it has involved a lot of messing around with arcane file formats and specialised software but popular email ‘client’ programs, like recent versions of Outlook/Outlook Express and Netscape Messenger etc., have taken the sting out of both sending and receiving them. Other email clients handle attachments with varying degrees of success, some email systems cannot handle them at all, but we’ll look at the problems and pitfalls in more detail in a moment. However, before we go any further, we’d better explain what a file attachment actually is.

The name says it all. An attachment is simply a file attached to an email. What makes file attachments so useful is that they can be almost anything, from a photograph or a spreadsheet to an encrypted document or a complete program, but as far as the client program sending or receiving the attachment is concerned, it is just a data and file what it contains is completely irrelevant. Unfortunately this is what makes attachments so dangerous, and a virus, contained within an attachment, can be activated as soon as it is opened; one careless click has infected many a PC.

If you are willing and able to receive attachments on your PC – and generally speaking it is good thing to have  -- then it is very important to have an anti-virus strategy, and stick to it! Some of the more advanced virus scanner programs can be set to automatically intercept all incoming emails and attachments and check them for infections, but they are only as good as their last virus pattern update and can easily miss newly developed strains. Rule number one, never open an attachment unless you are expecting it, you know exactly what it contains and it comes from a one hundred percent reliable source. Even then be cautious as some virus programs propagate by hijacking email client programs, sending copies of itself to all of the names in the infected program’s address book, so a viral attachment could just as easily come from a relative, friend or colleague.

Be especially wary of any file attachment with the extension ‘.exe’ as that indicates that it is a program, and it will run as soon as you click on it. The safest thing to do when an email with an attachment arrives in your inbox is to click on the attachment icon, choose the ‘Save it to Disc’ option and send it to a specially created ‘quarantine’ folder, where you can deal with it at your leisure, by contacting the sender for assurance, or run it through your PC’s fully updated virus checker.

Sending an attachment in Outlook Express and Netscape is very easy. In both cases there is an Attachment icon on the message window toolbar. When you have composed your message simply click on it and you will see a standard Windows file finder dialogue box. Locate the file that you wish to send, select it click OK and its file icon will be shown in the message Window. Send the email and any attachments in the usual way. Alternatively, open Windows Explorer, then the New Message window, and simply drag and drop files into the message window and they’ll be automatically included as attachments.

Now for some more of those problems mentioned earlier. A growing number of electronic gadgets can send and receive emails these days, including mobile phones, email telephones and TV Internet set-top boxes, hardly any of them can handle attachments, so always make sure that the recipient actually has a PC or Mac running one of the popular client programs. It’s also important to know that the recipient has suitable software with which to open or view the attachment. It’s no good sending a Word document to someone without Word on their PC. Unless specifically asked to send copy in a particular file format play safe and always send documents as plain text, which can be read by any word processor or Windows WordPad/Notepad. Photographs should always be in the .jpg (JPEG), or .TIF (tagged image file format) file formats, which won’t be a problem for anyone with recent versions of Outlook Express and Netscape; avoid sending pictures as .bmp (bitmap files) as they can be huge and take ages to upload and the recipient won’t thank you for it!

Some mail servers cannot or will not handle file attachments larger than 1 megabyte. Normally it’s not a problem, most JPEG image files are only a few kilobytes in size. However, if you think your attachments are going to add up to more than 1Mb you can set Outlook Express to break up the files into more manageable chunks, that the recipients mail server will accept. The option can be found by clicking on Accounts on the Tools menu, select the Mail tab, highlight the account you are using, then click Properties and select the Advanced tab. Under ‘Sending’ set the ‘Break apart messages larger than…’ to an appropriate size.

Finally, spare a thought for whoever you are sending the attachment to, especially if they live overseas or in a remote area. Internet access in some parts of the world can be slow and very expensive. In any case always warn a recipient that you are sending them a large attachment, just in case they don’t want it!

Next week – Installing a CD-RW drive

JARGON FILTER

BITMAP

Type of image file format (extension *.bmp) used by Windows and many other programs, quality is high because no compression is used, however bitmap files can be very large and are unsuitable for sending via email

JPEG

Joint Photographic Experts Group -- part of International Standards Organisations, responsible for devising software compression systems. Picture file format used for storing photographs, data is compressed thus saving space and reducing download times on Internet pages and emails

HTML

Hypertext Mark-up Language – hidden codes in text documents, web pages and emails that allow the reader to quickly move about the document, or jump to another, by clicking on underlined, ‘links’ which appear as coloured highlighted words or phrases.

TOP TIP

Here is another way to send a photograph with an email, by inserting it into the actual message. This only works when your email client program – we’ll assume you are using Outlook or Outlook Express – is set to send HTML (Hypertext mark-up language), and the person you are sending it to can receive HTML messages. Click on the New Message icon, go to the Format drop-down menu and make sure ‘Rich Text (HTML)’ is selected. Now all you have to do is compose your message as normal and when you come to the point where you want the picture to go click on the Insert Picture icon (it looks like a postcard), then use the Browse button to locate the image file. It will appear in the message window, as the recipient will see it. Finish your message and send it as normal.