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Common Access Card help for your
ersonal Computer



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Please know Microsoft plans to end support for Windows 10 on 14 October 2025




Windows 11 page


Utilizing your CAC on Windows 10 "can" be as easy as...

 Installing the DoD Root certificates and making sure the Internet Options are set correctly.

However, computers don't always cooperate with us.  So....

Here are my findings and solutions:

 Cannot send email in Windows 10 using Internet Explorer since Microsoft patch Tuesday around 14 March 2017

Information:  Edge is the default web browser in Windows 10.  Internet Explorer is on the computer and provides backwards compatibility for web pages that do not work with Edge.


My recommendation is to type: Internet Explorer into the Search the web and Windows / I'm Cortana / Ask me anything (box) in the lower left corner of your screen.  Once Internet Explorer appears, right click Internet Explorer and select Pin to taskbar.


Finding 1:  You upgraded from Windows 8.1 and were using your CAC with little to no problems, and now you can't access CAC enabled sites.  Keep reading for ideas to try:

Solution1 (built-In Smart Card Ability):  Uninstall ActivClient 6.2.0.x or 7.0.1.x by "Right Clicking" the Windows logo "4 squares" [in the lower left corner of your desktop], select Programs and Features (now called Apps and Features), find ActivClient in your list of programs and select Uninstall, restart your computer and try the sites again.  It may work, if it doesn't, try next Solution.  Dual persona (PIV) users might be able to access their email using the built in Smart Card Ability, your results may vary, if it doesn't read your PIV, you will need to follow Finding 1, Solutions 2 or 3 below.

Finding 1, Solution2 (ActivID):  ActivID ActivClient works great on Windows 10 computers and is available for Army users from links on the Army page.  All other people will have to get it from you respective branch or purchase it to try it on your computer.


Finding 2.  I can't access encrypted emails when using the Edge web browser

Solution 2:  The Edge web browser does not support S/MIME.  See my recommendation above to see how to use Internet Explorer to read and send your encrypted emails when using OWA / webmail.

Information (from Microsoft):  To understand the problem with OWA, Edge, and S/MIME you need to know the OWA S/MIME is an Active-X control.  By design Edge does not support Active-X (or Browser Helper Objects); this is good from a security perspective, but bad if you want to use OWA with Edge. Windows 10/Edge is a work in progress, Microsoft is planning to use other technologies to replace Active-X sometime in the future. In the meantime use Internet Explorer 11. 

Finding 3.  I can't sign PDFs (Portable Document Format) like I did in Windows 8.1

Solution 3:  To digitally sign PDFs, you need to use Internet Explorer, NOT the Edge web browser, and have Adobe Reader set as the default PDF viewer.  NO other PDF readers will allow digitally signing of forms.  This should happen automatically when installing Adobe Reader.  However, if it doesn't, here is how to change the default viewer:

Type:  "default" into the Search the web and Windows / I'm Cortana / Ask me anything (box) near the Windows logo at the bottom left of your screen. 

Click: Default Programs at the top of the list. 

Click: Associate a file type or protocol with a program

Scroll down to .pdf, if it shows Adobe Acrobat Reader, it is set correctly, if it shows some other program, select .pdf and click the Change program.. (button) in the upper right corner of the screen.  

"Adobe Acrobat Reader" should be in the list of choices, select it and then OK


Finding 4.  How do I get to Internet Options in Edge?  I can't find it.

Solution 4:  Follow slide 5 of


Finding 5.  Cannot see / select the Authentication / PIV certificate in Windows 10

Solution 5:  Windows 10 users will see the certificate selection differently than older versions of Windows.  Click More choices to see additional certificates.  Select the correct certificate and then click OK.

Windows 10 cert selection


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