10 tips for speeding up Outlook

Does Outlook's pokey performance have you gnashing your teeth with frustration? Try these simple fixes to give it a kick in the pants.

If you've used Microsoft Outlook for a while, you know that it can slow down... way down. In fact, when not looked after, Outlook can become nearly useless. Fortunately, there are several things you can do to make Outlook not only usable, but significantly improved. And none of these techniques requires a single configuration change to your Exchange server (IMAP or POP3).

Of course, some of these suggestions might seem to have a bit more "'duh" factor than others. But you never know what level of skills you're dealing with, so we'll cover all the bases. In the end, you should have a much faster Outlook experience.

1: Update Windows

Many people don't realize that with Windows updates, the updates for Microsoft Office are also "hidden." But it's not just the Office updates that can help speed up Outlook. Make sure you allow the updates to happen. Why? There are times when Microsoft might update Exchange. In some cases, those updates can either break or cause problems with the communication between Outlook and Exchange. Or Microsoft might issue a patch to the application to resolve a speed issue or security hole.

2: Download complete items

When you connect Outlook with either IMAP or POP3, you should have Outlook set up to download the complete message (instead of just the header). If you do this, Outlook won't have to sync with the server every time you click on a new item (as it will already be in the data file.) How you do this will depend upon which version of Outlook you're using. But basically, you're looking for the setting Download Complete Item Including Attachments.

3: Archive your Inbox

I can't tell you how many times I see clients with thousands upon thousands (and in some cases tens of thousands) of emails in their Inbox. This can cause serious issues, especially when using PST files. Instead of just letting those Inbox folders grow to outrageous proportions, set up auto archiving so that your Inbox retains only a portion of those emails. I like to tell clients to keep the current and previous months' email in the Inbox and archive everything else. When you archive, you effectively create a new data file, so Outlook doesn't have to strain against the weight of an oversize PST or OST file

4: Use Cached Exchange Mode

If you use Cached Exchange Mode in Outlook, you effectively take the data file from the server (PST) and cache it on your local machine (OST). This can go a long way toward speeding up your Outlook experience because Outlook doesn't have to read its data file across a network. Instead, all it has to do is read the locally stored data file. This option (obviously) is available only when connecting Outlook with an Exchange server.

5: Compact your PST file

When the Outlook PST file gets out of hand, a built-in tool can keep the size of that file under control. One of the issues is that even when you delete email from your Inbox, the size of the PST file may remain the same. If you're using Outlook 2010, you can go to Account Settings | Data Files and select the data file to be compacted. Once you've selected the file click Settings | Advanced | Outlook Data File Settings and click Compact Now. Depending on the size of your data file, this process can take some time.

6: Repair your PST file

Scanpst is often my go-to tool when Outlook is acting off kilter. It will scan through your data file and look for data inconsistencies and errors. Here's the thing about Scanpst — it's not always the easiest tool to find. Do yourself a favor and search through your C drive to locate the Scanpst.exe file. Make note of its location (usually within the Office installation folder). But be forewarned: This tool can cause PST files to become unusable. Make sure you back up that data file before you start the repair tool. Fortunately, should Scanpst find errors, it will prompt you to make a backup before it attempts to fix the errors.

7: Cut down on the published and shared calendars

Yes, it's easy to publish and share your calendars with others. The problem is, the more you do it, the more drag you're putting on Outlook. The more data Outlook has to share and pull down from the Internet, the slower it will perform. Sure, it's fine to have one or two shared calendars (and even more if you have a lightning-fast data pipe). Just know that the more data you have to push and pull, the slower your connection will be.

8: Disable RSS

By default, Outlook will sync RSS feeds from Internet Explorer to the RSS reader in Outlook. If you have a lot of RSS feeds bookmarked in IE, that syncing could easily bring Outlook to a crawl. Disable this feature (if you don't use Outlook as an RSS reader) from within Outlook 2010 by going to Options | Advanced and then unchecking both options under RSS Feeds.

9: Disable add-ins

How many times have you installed some program only to find it installed something else behind your back? This can happen to Outlook as well as Internet Explorer. Sometimes those add-ins can cause major Outlook slowdowns. To find out what add-ins you have installed in Outlook 2010, go to Options | Add-ins. Select COM Add-ins from the drop-down and click the Go button. The resultant window will list all add-ins available to Outlook. Search through this list and uncheck any that might seem suspect.

10: Fix ShoreTel Windows 7 integration

If you use the ShoreTel Communicator, you might notice some issues when trying to open and use Outlook. The problem lies in an incompatibility issue between ShoreTel and Windows 7. The fix is simple. Open up the Task Manager and look for a process called Agent.exe. Right-click that entry and click Properties |Compatibility. Choose the Run This Program In Compatibility Mode For option and then select Windows XP (Service Pack 3).

Other tricks?

There's no reason why anyone should have to struggle with a bogged down Outlook that will have you pulling your hair out strand by strand. These tips should help you enjoy a much speedier and reliable Outlook experience.

What other methods have you found for improving Outlook performance? Share your suggestions with fellow TechRepublic members.


Jack Wallen is an award-winning writer for TechRepublic and He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website

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