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Dealing with sending large files

A common problem we all hit at some point in our email lives, it that of sending a file that is larger than either your system or the person(s) you are sending to can handle.


Reasons why it is a problem:

With many email systems the first message has to be fully received before the 2nd one can. If the first message is large, then a recipient with a 'slow' link will just have to wait for it to download before the ones after it will make it through. Naturally this is a rude thing to put them through. Also if you are trying to send from a 'slow' link you will also suffer for it so the following will help you avoid your own frustration in addition to preventing others from getting angry with you.

'Slow' is always relative even in this context. There will always be a wide range of email access speeds so it will always be rude to assume that everyone enjoys the same high speed access you do. In late 2000, less than 30% of Internet access was with anything faster than dial-up and there are a great many places that just can't get any faster than that (eg, my parents place, no cable and even when ADSL gets there it won't be any faster than dial up, as of 2012).


How to avoid creating this problem

Most people have to trip over this problem at least once before they get to really understand the issue, so don't feel bad about it if this if the first time you have been referred here. Just make sure you learn this lesson before you really inconvenience someone you care about. As the steps to transfer information in a bandwidth friendly manner are not obvious, I shall attempt to list my best practices for doing so.

First step is knowing if the file(s) you are working with is large or not. To do this you need to know the measure of Size on computers and that is in Bytes and like the Metric system (aka System International) is expressed On Windows systems you can use Windows Explorer to View the file size.


A general rule: don't send files to large groups of people, just don't as this can readily clog a system up. Find some other way (list of methods later)

- if you are sending a file to someone else in the office,

often the best way is via a transfer directory that most offices do have set up

if a transfer directory is not available then think if the recipient ever gets their email remotely. if not then generally just go ahead and send it. and then make sure you don't keep that outbound message in you Sent Items folder (if you don't know about your Sent Items folder do ask your local admin as you should be familiar with it and how to use it)

- if you are unsure if some of your recipients are going to collect your message remotely or any of them are across the Internet then here are some things you can do to ensure that it is a painless experience.

- un-confidential images can often easily be posted of a web site either internal only or on the public net (eg. or place name with face at )

- learn how to check file sizes. In Windows Explorer, go to the directory the file(s) in question is(are), select 'View' from the menu, select 'Details' and you will see a size column on the right. Generally most people don't have a problem with files under 100KB, remote people will start having issues over 500KB, and many email systems will start having problems over 5,000KB.

- if you have to send files then you might want to learn about compression tools. PKZip was a common one from the DOS days, nowadays WinZip is the big one. Ask your local PC support people about it. Microsoft Office files (Word, Excel, PowerPoint) generally compress very well typically compressing to less than a quarter of their size. Of image files, BMP and TIFF formatted files will really shrink if saved as GIF or JPG. Note that any native compression your email client may have is only for local storage and not Internet transmission,if has to explicitly say that it is ZIPping to mean it is saving as a standard ZIP file.

- If you you've exhausted the above pointers and still really need to send large files , then investigate TransferBigFiles and other such file transfer services.
Flash keys or USB keys are a great way of moving lots of data fast and xkcd has proven that FedEx has a greater bandwitch than the internet (and other carriers certainly work as well).
Other things to consider are burning it to CD/DVD which most system have the capability of (though that is going away. Old school would be to check if you and your recipients have access to the same removable media such as Iomega ZIP drives or SyQuest drives as that is another way to move large volumes of data. Tape formats are sufficiently unstandardized enough that they are not worth the headache unless you are sure both ends are the same compatible systems. Your local support techs can help you with these options.

Last updated 2013-13-17 Copyright © 2000-2013 Andy Konecny andyweb @