If you are using a Mac and receive error code 0x80072f17 when trying to activate Office 365 below are some possible troubleshooting steps you can take to resolve the issue.
To fix the issue with error code 0x80072f17 I found that you need to reset all security certificates (ones that had a blue Plus sign!) to system defaults. This can be accessed through keychain access in applications.
The following solutions can be found from the apple site.
The Keychain holds passwords and certificates used to create authenticated connections from apps such as Mac App Store. If the issue still happens after following the previous steps, try editing your Keychain.
- Open Keychain Access located in /Applications/Utilities/
- Select Certificates from the left hand column under Category
- Type Class into the search field in the top right corner of the Keychain Access window and press return.
- Look through the list of results for any certificates that have a blue + over the icon.
- Double-click on a certificate that has the blue + over the icon to ‘Get info’ on the certificate.
- Click the disclosure triangle to the left of the word Trust to reveal the certificates permissions.
- Change Secure Sockets Layer (SSL): to ‘No Value Specified’ then close the window.
- Confirm the Administrator password in the window that will appear.
- Double-click on the same certificate that was opened in step 5.
- Again Click the disclosure triangle to the left of the word Trust to reveal the certificates permissions.
- Change When using this certificate: to ‘Use System Defaults’ then close the window.
- Again confirm the Administrator password in the window that will appear.
- Repeat steps 5 through 12 for any certificates that have a blue + over the icon. (Generally there are only one or two that will need to be edited.)
- Restart the system and test for the issue.
Important: If the certificates do not allow themselves to be modified as is needed in steps 5 through 11, you need to reinstall OS X. After reinstalling, attempt these steps again.