Hi @evan,
I created and encrypted a pdf file in Word, and send a message with this pdf attachment.
The mail flow rule did block the message.
To me I suppose the cause may be with the pdf file's format, as according to this link: Use mail flow rules to inspect message attachments in Exchange Online
This condition matches messages with attachments that are protected by a password. Password detection only works for Office documents, .zip files, and .7z files.
Is this issue occurring to all encrypted pdf files?
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