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This feature comes disabled for existing customer and is enable by default for new install. This allows existing customers to transition on their own timeline to the new portal.
How-To turn on Checkout Request type
Checkout requestype is hidden in old installations under hidden group. Therefore, all you need to do is to navigate to Project Settings > RequestTypes > CheckOut > … >Edit >Edit
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Modify the group where Checkout can be visible in the portal. The default group is general.
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All the fields configured in the requestType will be visible to customer in the portal. Be sure to customize the Checkout RequestType description and Icon to make it your own.
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Head over to the portal and test out visibly of Checkout.
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