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If you are upgrading from 5.3.3 or older, you must upgrade to 5.4.0, 5.4.1, 5.4.2, or 5.4.3 in order to upgrade to the latest version. Upgrading from Concerto is only supported by upgrading to 5.4.0 prior to upgrading to the latest version. Refer to your version in the Upgrading chapter of the DTP 5.4.3 documentation for details.
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