Who can help me decipher or decode da contents of this email?

Can anyone please decipher the contents of this email? I keep getn email saying message I sent was undeliverable when I hadn’t sent any messages. I got all broke down but the content and want to see what messages I supposedly sent or try figure out who using SMTP:Received:From:Subject:Date:To:Message-Id:MIME-Version:Content-Type:Content-Transfer-Encoding; b=aRX9cTL4EFDo7gphDuetIYDRpT/vNyeaTra6kBnZ+pi1ZWGSLtxvD+yuSJb+S61hlnFf5LJHiPd686IgNZ+WLCtdQnQ/gD5qEN8mp+DrmdwiagRC4UM3+vz6fdlCjw+RWkdZ1MHzrPDuX+9OAYda4zW7xVxkVhWCIy0VCyFLcaQ=
X-Yahoo-Newman-Id: 545264.21362.bm@smtp202.mail.bf1.yahoo.com
X-Yahoo-Newman-Property: ymail-5
X-YMail-OSG: RqEr6ekVM1nWFw_GJjg0g5JCUNQPWvnCv8Xpdm7MN1D1FHS
rqRfHIIMvYkuz8Ph42NNT.Ss5YEesef5FXtrV407pdKVC2FDJG0nJpPWGdlt
0YWaCXoHCrTktjX1fNlMMMsFetM7rBLwpMATcL05I7.Q1UC9FOkzAdbcRK1Q
8mFtJ_UOjBBm3MeX342J128bSgmYkc3HekZ4m.V1YwSsxSTZMmPp_tYqagDz
nymlONbV4k64etcqhAmM6pABooCr_zNyFSYiRsaz4QxPtobgjgqF12LQ8cKE
7xQxmFukhWLunDqtzaSaG4sAGVyIhzAuW4UOAcx57fhLiUqUXOzRIpsoHZkQ
FeO0fUzFBD5YZe2I_Y37DE31FJxAisYL7SQbXxTCDdj14yGR7QMjYiB6hWGm
93FyhQrKXkM3dDz5w32rySjgrqXEkzSZR5N_rz4REUHfVcAinryaUw1MkmM2
QIO03x3wQdpYX8MuGBpoqTTmVW.rGsuE6XoDFDHNIFYQ4mZinxDfy
X-Yahoo-SMTP: 8JeNIfuswBB1oiPZ_.bmYZ4z6ugEmfE

Someone may be spamming using your email address, or your computer may be infected with malware.

I don’t see the IP address that would normally be in the header. It would normally be something like “Received: from some.domain.name ([12.12.123.123]:12345)”. If the IP address corresponds to your computer or network, your system may be infected and sending binary encoded spam. If the IP address isn’t yours, it’s just someone else sending spam using your email address. Not a whole lot you can do about that, unfortunately.