I am using MailKit/MimeKit 1.2.7 (latest NuGet version).
Deleting an email with the ImapClient is pretty easy ...
client.Inbox.AddFlags(uniqueId, MessageFlags.Deleted, silent: true);
... if you know the emails UniqueId or its Index.
In my case, I don't know either one nor the other. All I have is the message itself (MimeMessage) ad its MessageId.
I was hoping that MessageId == UniqueId, but obviously this is not the case.
Do I have any chance to delete an email by just having the corresponding MimeMessage/MessageId?
You could try doing something like this:
var uids = folder.Search (SearchQuery.HeaderContains ("Message-Id", message.MessageId));
folder.AddFlags (uids, MessageFlags.Deleted, silent: true);
Ideally, though, you'd keep track of the UniqueId
that you used to fetch the message so that you can just use that value.