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To add the code as part of a QR code:
Go to Site Administration > Courses >
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Manage certificates
Click on the edit icon next to the certificate in question
Under the "Other Options" section, set "Print Certificate QR Code" to "Yes"
We also recommend that you set "Print QR Code in the first page" to "Yes" as well (unless you want your certificate to contain multiple pages)
If you click on the "Show more..." link still in the "Other Options" section, there are two fields that allow you to position your QR code:
Certificate QR Code Horizontal Position
Certificate QR Code Vertical Position
Click on the "Save" button at the bottom of the page
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To add a code in text format:
Go to Site Administration > Courses >
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Manage certificates
Click on the edit icon next to the certificate in question
In the "Certificate Text" area, enter {CERTIFICATECODE} (with the curly braces)
Click on the "Save" button at the bottom of the page
To verify the authentication of a certificate that has a QR code:
Using your smartphone, scan the QR code.
Many smartphones will allow you to scan the QR code simply by launching your camera and pointing it at the QR code. Other (usually older) phones may require that you install a QR reading app on your smartphone.
Go to the URL provided by the QR reader
Click on the "Verify Certificate" button
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To verify the authentication of a certificate that has a code displayed in text:
Go to the site in question.
Go to /mod/simplecertificate/verify.php
For example, if the certificate of completion was issued
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by My Dual Code, which is located at https://my.dualcode.com, you would go to https://my.dualcode.com/mod/simplecertificate/verify.php
Manually enter the code in the text area
Click on the "Verify Certificate" button
Important Notes
The QR code approach is generally the preferred approach if someone needs to verify the authenticity of the certificate out in the field. Since most people nowadays have a modern smartphone, they can easily verify the authenticity of a certificate by scanning the QR code, which is easier than typing a 30-40 digit unique code.
The QR code also displays the unique code near its bottom. This code is the exact same code that would be printed if you were to use the {CERTIFICATECODE} approach.