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Question: Apple Mail is Duplicating Mailboxes

Since the supplementary Update of High Sierra 10.13.3 I have had problems with Apple Mail.

1) Jamming randomly when deleting emails - gets jammed with message eg - 'moving messages 1 of 10'

2) Duplicating Mailboxes and sending email to these rather than my existing ones.

3) Attaching 'new emails' to old ones. The header and subject line from an old email and the body and text is a new email.

I would love if someone has a fix for this.

MacBook Pro with Retina display, iOS 10.3.3

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Mar 11, 2018 9:23 AM in response to nzjo99 In response to nzjo99

Try rebuilding the mailbox(s).

Rebuild mailbox

If that doesn't work, try re-indexing the mailboxes. This can take awhile if you have a lot of mail.

Reindex messages For El Capitan, try looking in V3. Sierra use V4. High Sierra use V5.

Reindex messages (2) See post by Linc Davis

Mar 11, 2018 9:23 AM

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Mar 21, 2018 1:50 AM in response to Eric Root In response to Eric Root

Thanks Eric, I have already tried that to no avail. What is happening when an email comes in where there is a rule it makes a new read only mailbox and disregards the old rule to put in the existing box. Really weird and I'm not liking all these extra mailboxes.

Mar 21, 2018 1:50 AM

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Question: Apple Mail is Duplicating Mailboxes