$wgPasswordSender = "no-reply@myht.org";
You need set your contact address in Reply-To: email field.
Or other method. You can do full SMTP settings to outer service(SMTP).
see detail mediawiki document. (I don't know well)
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Nobuhiro YASUTOMI (MySite Users Webmaster)
Nobuhiro YASUTOMI (MySite Users Webmaster)