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When you have file Xero/etc/certs/magenest.cer, copy and paste them into X509.
You will see the Xero accounting interface after you've done the last step but now we need to continue our setup, go to this site: https://app.xero.com/Application to create the Application.
Choose the application mode (usually is Private), application name (the name for the application is not very important), choose your organization (this is where the Magento 2 data will be synced into). After After that, check the information again then check on "I have read and agree to the Xero Developer Platform" & click click Save.
If everything goes right, you will see the following content. By now we have done everything on the Xero site, now move to your magento 2 backend but don't close this site.
Click on "Show" button to show the Consumer Key & Consumer Secret.
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