This error affects Exchange server users with a large number of folders in their profile, either in their mailbox, public folders, or SharePoint lists. In most cases, you won't have a problem until you exceed approximately 1,000 folders, or a gigabyte of space is used.

Outlook works fine for a little bit (5-10 minutes) before users start getting this error:

Task 'Microsoft Exchange' reported error (0x8007000E) : 'Out of memory or system resources. Close some windows or programs and try again.' Cannot display the folder. There is not enough free memory to run this program. Quit one or more programs, and then try again. Cannot expand the folder. There is not enough free memory to run this program. Quit one or more programs, and then try again. Cannot expand the folder. There is not enough memory available to perform the operation.

When they close Outlook and reopen it, they can again work for a few minutes before the errors kick in. The error appears whenever clicking or expanding a folder (public folder or mailbox folder) except for the Inbox. When the error occurs, mail in the Outbox also doesn't get sent until Outlook is restarted.

The Solution

You have two options to avoid this problem: either disable the Download Public Folder Favorites option, or keep the number of cached public folders favorites under 1,000 (or low enough to avoid the error message.) .

You can typically reduce the number of public folder favorites by deleting them by using the Outlook client.

To disable the Download Public Folder Favorites option:

1. In Outlook, click File, Account Settings, and then click Account Settings.
2. Double click on your Exchange account or select it and then click Change.
3. Click More Settings.
4. On the Advanced tab, clear the Download Public Folder Favorites check box.
   
5. Click OK and return to Outlook.

You'll need to restart Outlook for these changes to take effect.

In some cases in which you have too many public folder favorites, you may receive an error message when you attempt to delete the folders in Outlook. When this occurs, you'll need to use MFCMAPI to delete the folders.

1. Run MFCMAPI.
2. On the Session menu, click Logon.
3. Select your Outlook profile name, and then click OK.
4. In the top pane, locate the line that corresponds to your mailbox, and then double-click it.
5. In the navigation pane (left-side pane), expand Root - Mailbox, and then select the Shortcuts folder.
6. In the details pane (right-side pane), locate the PR_FOLDER_CHILD_COUNT properties. The Value column contains the number of public folder favorites.
7. If you want to delete all your public folder favorites, right-click on the Shortcuts folder in the navigation pane, select Advanced, and then select Empty items and subfolders from folder. Keep the default options, and then click OK.
8. If you want to delete specific public folder favorites, follow these steps, expand the Shortcuts folder in the Navigation pane, right-click on the Public Folder favorite that you want to delete, and select Delete folder. Keep the default options, and then click OK.

Other Possible Causes

Office for Mac
Performance problems when you try to access folders in a secondary mailbox in Outlook 2010