Users in an on-premises Exchange Server environment or in Office 365 who use Internet Explorer 8 to access Outlook on the web (formerly known as Outlook Web App [OWA]) experience slow performance when they perform common tasks such as the following:
Read new mail
Send and receive mail
Select recipients from the global address list (GAL)
Additionally, a "Waiting for <URL>" message might be displayed on the Internet Explorer 8 status bar. This message does not go away even after the user presses the F5 key to refresh the browser window. This message indicates that Internet Explorer 8 is continuing to load Outlook on the web components or data.
We strongly recommend that users upgrade to the latest version of Internet Explorer.
For more info if you have Office 365, see System requirements for Office. Microsoft will continue to support Internet Explorer 8 and Office 365. However, the user experience and support experience will be limited.
If you can't upgrade to the latest version of Internet Explorer and must continue using Internet Explorer 8, use the light version of Outlook on the web.
To set up the light version of Outlook on the web for all users in your Office 365 organization
Click Admin, and then click Exchange to open the Exchange Admin Center.
In the navigation pane of the Exchange Admin Center, click permissions, and then click Outlook Web App policies.
In the Outlook Web App policies dialog box, click features, clear the Premium client check box, and then click Save.
Note These changes may take several minutes to take effect.
At this point, all users in the Office 365 organization who use Outlook on the web will be presented with the Outlook on the web light experience. Users won't be able to switch to the Outlook on the web premium experience until the admin reverts the changes that were made to the Outlook on the web policy in the Exchange Admin Center.
To set up the light version of Outlook on the web for one user in your Office 365 organization
Click Settings (), and then click Display Settings.
Click Outlook Web App version, select the Use the light version of Outlook Web App check box, and then click OK.
To return to the Outlook on the web premium experience, the user has to clear the Use the light version of Outlook Web App check box. The user will be presented with the Outlook on the web premium experience the next time that he or she accesses Outlook on the web.
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