When you have created your new org environment, install the latest pre-release version of PosiPay as follows:
Check the Pre-release Notes page for the latest package versions
Click on the link to open the pre-release notes
Copy the URL and append it to your primary domain name in the browser address bar as follows:
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Press Enter and it will to load an installation screen, similar to the one in the image.
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Select "Install for All Users" and acknowledge. Verify the version number and click Install.
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When you click Install, a message will appear asking if you want to grant access to third parties. To approve, simply click YES. Check that the details match the image provided.
Follow the instructions until you have successfully installed the package. These steps can also be used when upgrading a package version.