Email filtering- please help

[jaguarpaw43]

I sent an email to my history teacher with 2 jpeg files. I then received an email from Microsoft Outlook saying this;
"The C2K email filtering policy has been applied to this message in O365. This is an automatically generated message, please do not reply to this address as it is an unmonitored mailbox. Please contact C2k Helpdesk if you would like this message released."
Does anyone know what this means? Has the email been received or do I need to send it again?

[casper]

Can you upload the jpegs to Google Drive or OneDrive and email the link to your teacher? Just explain that you're not sure if he/she received them as they were blocked the first time.