Claudio Sakaguti wrote:
> Hello All!
>
> Before, we used Redmine 3.4 and we could send emails with subaddress in BCC to open a new issue in the desired Project.
> But after upgrading to version 4.1.1 this does not work anymore.
> For example, before we could send an email with BCC:redmine+kitchen@email.com and the email would land on the Kitchen project.
> But after upgrading to version 4.1.1, the BCC:redmine+kitchen@email.com will arrive at the default project "House".
> If we send as To: or CC:, no problem.
>
> Could you please help me?
>
> Our system:
> Environment:
> Redmine version 4.1.1.stable
> Ruby version 2.5.8-p224 (2020-03-31) [x86_64-linux]
> Rails version 5.2.4.2
> Environment production
> Database adapter Mysql2
> Mailer queue ActiveJob::QueueAdapters::AsyncAdapter
> Mailer delivery smtp
> SCM:
> Subversion 1.14.0
> Git 2.27.0
> Filesystem
> Redmine plugins:
> additionals 2.0.25-master
> redmine_checklists 3.1.16
> redmine_ckeditor 1.2.3
> redmine_custom_js 0.1.1
> redmine_dashboard 2.7.1
> redmine_issue_templates 1.0.4
> redmine_lightbox2 0.5.1
> redmine_revision_branches 0.3.2
> redmine_theme_changer 0.4.0
> redmineup_tags 2.0.8
> sidebar_hide 0.0.8

Found the solutions within our team.
The problem was the email system we where using, Zimbra.
Zimbra removes BCC from headers. Looks like BCC is used by Zimbra for other means.
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