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Users are forced to join Lync meetings with the Lync Web App in Windows 8.1 Preview

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Users who have Windows 8.1 Preview installed are forced to join Microsoft Lync meetings through the Microsoft Lync Web App even though Microsoft Lync 2010 or Microsoft Lync 2013 is installed. Users may see the following notification message in Internet Explorer 11:
This webpage wants to run 'MeetingJoinHelper Class' which isn't compatible with Internet Explorer's enhanced security features. If you trust this site, you can disable Enhanced Protected Mode for this site and allow the control to run.

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In the recent Windows 8.1 Preview update, Enhanced Protected Mode is enabled in Internet Explorer 11 by default. Enhanced Protected Mode blocks all add-ons that don�t comply with certain requirements.

If you see the notification that's mentioned in the "Symptoms" section, click Run add-on. Lync then starts and successfully joins the meeting.

If you don�t see this notification, or if you miss it the first time that it's presented, you have the following options:
  • Re-enable the Lync Browser Helper add-on in Internet Explorer 11. To do this, follow these steps:
    1. Go to Settings, and then click Manage add-ons.

    2. Select the MeetingJoinHelperClassadd-on, and then click Enable.
  • Disable Enhanced Protected Mode in Internet Explorer 11. To do this, follow these steps:
    1. Open Internet Explorer from the Desktop.
    2. Click Settings, and then click Internet Options.
    3. Click the Advanced tab, scroll down to the Security settings, and then clear Enable Enhanced Protected Mode.
    4. Restart the computer, and then try to join the Lync meeting again.

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Still need help? Go to the Office 365 Community website.

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Keywords: o365062011, o365022013, o365, o365e, o365a, o365m, pre-upgrade, after, upgrade, kbgraphxlink, kbgraphic, o365p, KB2867734

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Article Info
Article ID : 2867734
Revision : 4
Created on : 9/10/2013
Published on : 9/10/2013
Exists online : False
Views : 413