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Open the system where Int4 Suite add-on is installed
Go to System → Status
In the new window click on the details button next to the Product Version.
Check the INT4 component to confirm the main release version installed
(optionally) How to check Int4 Suite minor release version
Go to transaction SE24 in the system where Int4 Suite add-on is installed and display the details for the object type: /INT4/IFTT_IF_VERSION
Go to the attributes tab and check the attribue GC_IFTT_VERSION
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