mail you have not sent sounds like the result of malware.
Scan with the following (all free) Malwarebytes anti malware; and Superantispyware; and A-Squared. These should find and remove any nasties that you've picked up.
Surface Pro 5 News - release date, UK price, features, specs
Animator Emanuele Kabu’s psychedelic video is a stunning tribute to Lisbon city
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