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As the only existing work-around, Microsoft always sends invites unencrypted. However,
You can configure S/Notify does not currently check outgoing emails for invites. Please let us know to send emails unencrypted when they include ics attachments. Refer to https://savignano.atlassian.net/wiki/spaces/SNOTIFY/pages/2624880659/Advanced+Settings#Key-skipEncryptionRegex for the relevant setting and reach out to our service desk if you run into this problem.
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