Email's attachment won't be exported correctly.

[XiaoMouR]

I try to export an email's attachment(Zip archive), but that exported file could not be unzip successfully.I compare this file to which exported by emali client, like follows:
50 4B 03 04 14 00 08 00 08 00 EF BF BD 02 29 4A -->export by enmime
50 4B 03 04 14 00 08 00 08 00 C2 02 29 4A 00 00 -->export by email client
It's clearly that the byte 'C2' transfers to 'EF BF BD 02', I also check the implementation of Part's Read method:
return p.utf8Reader.Read(b)
OK, maybe it causes the issue when I need to read a binary file. So can export a METHOD for read the decoded binary content?

[jhillyerd]

I was able to write a test to reproduce this in 3dae741 - the only catch is that the attachment had to have a charset encoding header - which a ZIP file should not. Can you check the email that triggered the bug and confirm?

[XiaoMouR]

Yes. The reason you point out triggered the bug.
BTW, I have tried to construct the email example triggered the bug in my repo, but too busy to make me forget to PR it😫.