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By blocking these cookies the merchant's shop looses the information (e.g. SessionId) when the consumer has been redirected to the Computop Pay-Jet payment pages and is returning back to the shop after the payment has been completed.
Possible solutions
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Pay-Jet Paygate parameter "Custom"
You can use the Computop Pay-Jet Paygate parameter "Custom" to pass any customized parameter (like sessionId or more) to Computop Pay-Jet Paygate and Computop Pay-Jet Paygate returns your "Custom"-values when consumer returns to your shop.
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With the first redirect the web browser ignores the stored cookie – because that redirect was initiated by a third party Computop Pay-Jet Paygate – and the sessionId is lost.
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