CYBER NOTES September, 2005 by Dave Benore

Email Attachments and Why Some Will Not Open

Sometimes when opening an email attachment, things just don’t work. The file will not open. Some kind of error message appears that says “what program do you want to use to open the attachment?” What in heck is going on?

A little background: When a person creates a file by saving it, for example a letter written by the WORD program, that file does not contain simply the alphabetic characters used to type the letter. All of those alphabetic characters are encoded into strings of binary numbers, 1s and 0s, because that’s what the computer understands and what it saves on a disk. When one wants to look at the letter, the program “decodes” the strings of 1s and 0s back into what was originally typed. It’s kind of like you typed the letter in English but the computer saved it in Eskimo! The computer translates it back into English when you want to read it.

Now the next part: All word processing programs don’t use the same encoding. Each different program can be expected to use it own “code”. So if you receive a file attached to an email written by one brand of word processor, but you have a different brand, you probably will not be able to read the file. It won’t open.

Each file name has an extension associated with it. It is 3 letters/numbers following a period after the file name. (Some computers do not show you the file extension unless specifically configured to do so. That’s another story, as they say.) When you try to open an email attachment, the filename extension tells your computer what program created the file. Your computer then looks for that same program on your computer. If it finds it the file opens and you can read it. But if you don’t have the same program, the computer doesn’t know what to do. You get the error message.

Another complication can occur when the program versions are different. Sometimes you may have an older version of the program that was used to write the email attachment. You have the right program but an older version, so the decoding still does not work correctly.

Some of this stuff makes you want to tear your hair out. But for all the problems of learning to use home computers, they still open up a whole new world to those who use them. Ask the man, or woman, who owns one! Happy computing!

(Beginning Computer classes, open to all, are resuming at VOCA in October. Please see the Village of Oak Creek Community Events Calendar in this paper.)