If the certificate is signed by a trusted CA authority and the authority is on list of trusted authorities in SAP system (transaction STRUST), this step is not necessary. If the certificate is untrusted or self-signed, it must be imported as trusted to SAP, transaction STRUST. The indication the certificate is untrusted can be found in ICM trace file in SAP (transaction SMICM, menu Goto -> Trace File -> Display End), scroll in search for SSL errors.:
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To trust the certificate, it must be imported to an appropriate store in SAP in Trust Manager (transaction STRUST).
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