Installing S/MIME for Internet Explorer
Download and install S/MIME
https://ow2.res.office365.com/owasmime/20.19.701.1/OwaSmimeEdgeExtension.appxbundle
Check Internet Explorer settings
- Go to “Tools” and select “Internet Options”
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- Go to the “General” tab and click “Delete”
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- Make sure the checkboxes are checked as per the image below and press “Delete”
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- Go to the “Security” tab and click “Trusted Sites” and then click on “Sites”
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-Go to “Add this website to the zone:” and enter the URL for your Webmail/OWA server, click “Add” and then “Close”
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- Go to the “Content” tab and click “Clear SSL state” and then click “OK”
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- Go to the “Connections” tab and click “LAN Settings”, uncheck “Automatically detect settings” and click “OK”
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- Go to the “Advanced” tab, scroll all the way down and make sure the following “TLS” settings are checked:
“Use TLS 1.0”
“Use TLS 1.1”
“Use TLS 1.2”
Make sure there is a check on “Enable Enhanced Protected Mode” and click “OK” to close the window.
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- Close your “Internet Explorer” browser, re-open, go to your OWA site and login.
- Double click on an encrypted message to open the message on a separate window. If unsuccessful please open an ACS Get-Help ticket.