Get all the latest Computing Tips from our RSS feed

Mailbox Management - How to reduce the size of your Outlook Exchange Mailbox

It is time once again to remind users how important Outlook mailbox management is. It is necessary to keep the Exchange server functioning properly. This Computing Tip will show you how to manage your mailbox and illustrate several areas which will cause a mailbox to grow and how to rectify those areas. Those areas are: Managing Your Outlook Mailbox, Delete Old Messages, Delete Messages With Attachments, and Delete Sent Items. I would also like to preface this document by stating that we do not want to limit productivity or interfere with business practices. Rather, our intention is to bring light to a potential problem and have people take steps that they can to help remedy the issue.

Special thanks to Kevin Brinnehl, System Administrator, for writing portions of this tip.

Managing Your Outlook Mailbox

Begin by checking the size of your Mailbox. Click on Tools>Mailbox Cleanup.

Next click on the View Mailbox Size button. Users should try to keep their mailbox around 250 MB, although some users do have larger mailboxes.

Mailboxes fill up for several reasons. Here are a few reasons and solutions:

• The delete button is seldom used! Delete old messages, especially personal e-mail, e-mail announcing events, and e-mail sent to say thank you. This is true for both your Inbox and Sent Items folder. Keep in mind that your messages won’t actually be deleted until you empty your deleted items folder.
• E-mail with attachments uses up a lot of space in your mailbox. Since you already have the original file that is attached to the e-mail you send, you can delete those messages. If you need a copy of the e-mail itself, make a copy of it without the attachment. For incoming e-mail with attachments, save the attachment to your file storage disk, and then delete the e-mail. There will be e-mail that has information in the body of the e-mail that you shouldn't delete. For those messages, just keep the message. If you delete most e-mail with attachments, the size of your mailbox will be manageable.
• E-mail messages that include images use a considerable amount of space. For example, the Computing Tip of the Week is rather large because of the images used. Since it is archived on the web, you can delete the message after you read it, but still have access to the information.
• DO NOT hit Reply All every time you reply to an e-mail. Reply All is to be used for conversations that everyone in the group needs to hear. There are many instances where folks hit Reply All to say "Thanks", or to respond to the sender instead of the whole group. This is very important when an e-mail is sent to large groups like campus lists or department lists. There is nothing more annoying than being copied in on a conversation that has 20-30 message threads and none of them apply to the group, let alone to you. Use Reply All only when appropriate.

Delete Old Messages

Many people use Outlook as a historical reference. This is not necessarily a bad thing as old messages can come in quite useful every now and then. You can ask yourself, "Do I really need every message that was sent to me from 1996?" If you know you can clean out some old messages, here are the steps to do so.

1. In Outlook, go to Tools and then choose Mailbox Cleanup.



2. You should now see a window like the one pictured below. In this example, I am going to search for any message older than one year. Select "Find items older than" by clicking the radio button. Next enter the desired number of days. Once that is done, click Find. This will allow you to delete messages based on their age.



3. You will now see a window like this one. Outlook automatically sorts the messages by date so you can scroll down to find the oldest messages. From here you can delete all of your old messages. To delete multiple messages, click on the first item you want to delete. Then hold the Shift key and click on the last item you want to delete. This will select all of the items in between your two clicks, which will allow you to delete multiple messages at a time.

Delete Messages With Attachments

This is, by far, the primary contributor to your mailbox size. The reason for this is that the attachment still takes up space on the Exchange server and counts towards your final mailbox size. We highly recommend, especially for very large attachments, that you save the attachment to your z: drive and then delete the message. There are two methods that you can use to find messages with attachments.

Method 1 - Mailbox Cleanup Utility

1. Open the mailbox cleanup utility as outlined in the previous section.
2. This time, you will want to click on "Find items larger than". In this example, I am searching for items that are larger than 5 Megabytes (which equals 5000 kilobytes). You may not know or even care what a megabyte is. That's OK. Just keep in mind that anything over 5000 or 10000 kilobytes is a fairly large message so you would be pretty safe starting with those numbers.
3. Delete any files that you can.

Method 2 - Using the Advanced Find Feature

1. Begin by clicking on your name under "All Mail Folders". This will take you to Outlook Today.



2. Next, go to Tools and then click "Find > Advanced Find."



3. When the Advanced Find window opens, click on the "More Choices" tab. Then click the second box, "Only items with:" in the window as is shown below. Then click "Find Now." This will find any message that has an attachment with it.



4. Delete any messages that you can.
5. In some cases you might want to save a message you sent with an attachment, but don't need to save the attachment. To do this, open the message by double clicking on it. Then "right click" on the attachment and select "Remove". This will remove the attachment from the message, but allow you to save the original message.

Delete Sent Items

This is another very big contributor to your mailbox size both due to the number of messages in the folder and, once again, attachments. The easiest way to clean out the Sent Items folder is do to it by date. By default, when you click on the folder the message are already sorted by date. You can then scroll down and delete messages after a certain time period.

Remember these tips are archived on the web, so after you read this e-mail, delete it! Make sure though that you have the web site bookmarked in your browser.