From the Outlook start and exit option, check Empty Deleted Items folder when exiting Outlook and OK to apply.

Try these tips for a faster, more organized approach to keep your mailbox smaller and easier to work with.

Note: With the move in many organizations from Exchange Server (localnetwork) to Exchange Online (cloudOffice 365), the following steps will be less important as storage space is dramatically increased.

And, you can still cleanup your Outlook mailbox size if you are running Outlook as a stand-alone (POP3) version.

Caution: Before starting these steps, take the time to backup your Outlook.pst file (stand-alone version) which is usually found under the Outlook Files folder in Documents.

The following steps apply to Microsoft Outlook 2016, Outlook 2013 and Outlook 2010: 1.

Mailbox Cleanup The best place to start is to open the Mailbox Cleanup tool.

First, choose the View Mailbox Size option which scans the size of your mailbox and all of the subfolders.

This is a great way to target which folders are the biggest contributors to your large mailbox so you can clean these up first.

When connecting to Exchange, youll see a Local Data and Server Data tab.

Only look at the Local Data tab; cleanup changes you make will automatically take place on the server as well.

Next, pick the options to Find older or larger items which you can delete directly from the results to cleanup the Outlook mailbox size.

Depending on your archive settings (see Archive Older Messages below), you can also run an AutoArchive.

Finally, check the size of the Deleted Items folder and Empty the folder if you want (specific options detailed below as well).

If available, one option is to view and delete multiple versions of items in our mailbox.

Move Messages to Your Personal Folders If youre accessing Outlook from Exchange, another way to reduce the Outlook mailbox size is to move Outlook items to your Personal Folders.

This option may not be available to you as many organizations have moved away from supporting Personal Folders.

Even though the messages you move to Personal Folders are no longer counted in the size of your mailbox, the Personal Folders file (outlook.pst) is stored on your local hard drive and is not accessible remotely.

Archive Older Messages Another useful maintenance step is to periodically archive your Outlook folders.

If you are accessing Outlook from Exchange, you may not be able to change archive options as archiving is often controlled by system administrators or a third party program.

Setup your archive preferences under the Info Cleanup Tools Archive option.

The archive.pst file can be created and updated at any location you specify, usually your local hard drive.

Archived items are removed from your Outlook mailbox size and moved to the archive file based on the settings you determine.

Just as with the Personal Folders file, your archived items are not accessible remotely; the file should be backed up on a regular basis.

Empty Deleted Items Quickly clean up your deleted items by automatically emptying the Deleted Items folder when you exit Outlook.

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