Microsoft Outlook for Mac - No subject headers (transfer encoding)

Microsoft Outlook for Mac - No subject headers (transfer encoding)

I am thinking of switching from Apple Mail to Outlook for Mac.

I add my zoho mail account to Outlook but am getting some duplicate sent items (with no subject), with garbage above the message, for example:

--Apple-Mail=_03C44C4A-7DA9-4941-8604-C007F4D0D839
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain;
charset=utf-8

See screen grab of mail list.

Why is Outlook doing this, all the sent mail looks fine in Apple Mail?

I am using latest versions of everything.