I have tried to download email from an imap account successfully using vb.net and EAGetMail, emails are saved to a folder as .msg. The problem is when I open one of those files with Outlook (tested only with 2016 version) and I try to reply to all, from address appears on to destinations. If I try that with a msg file saved by Outlook not by EAGetMail the reply to all is ok and from address doesn't appear on to destinations.
I'm using evaluation version of EAGetMail, ¿is it a limitation or a bug?

thanks for reporting this problem, we will do a test and will back to you at tomorrow.

Hi, we have tested it. When outlook save the email, if the sender is an account existed in outlook, the message will be marked as self-sent, so when you click reply all, from will not be included in the destinations, however, when you use EAGetMail save the email, EAGetMail doesn't know if sender is an account existed in local outlook, so when you click reply all, from will be included in the destinations.

That is not a bug or limit.

Thanks, that solves the question. It would be possible to include an option on a future version to mark email as self-sent? Something like this:

Ok, we will consider to add this feature at next version, but it cannot be done in very soon.

This happens because a saved MSG file is not really an email message that's in your mailbox. When you open an MSG file and you click Reply All Microsoft Outlook thinks it is a file it does not think it is an email from your mailbox. As a result Microsoft Outlook may put the address in the To field it may put the From address of the MSG file in the To field. This is why you get this problem with MSG files in Microsoft Outlook.
Why this happens:
MSG files don’t retain full account context (like the original mailbox or sending account), so Outlook can’t properly map the reply fields.
Workarounds:
• First drag the MSG file into your Outlook mailbox folder, then open it and click Reply All.
• Or manually correct the To/From fields before sending.
Better approach:
Use a tool like Softaken https://www.softaken.com/msg-suite  to import MSG files. This way replies will behave normally.
• You can process MSG files, at once.
• It supports conversion without any data loss.
• The tool keeps all email properties intact.
These properties include attachments, formatting, subject sender details and timestamps. The tool also provides a demo version that allows you to convert a limited number of emails per folder.