iOS 18.3.1 and email sync issues

[robberthiaume]

I have a location that iOS devices on 18.3.1 are having issues syncing email with O365.  It is only affecting those devices that are at iOS18.3.1.  Has anyone else experienced this?

[RaphaelL]

Hi ,

Are you using a MX ? Any content filtering applied ?

[robberthiaume]

I am not using an MX, I have a Fortinet 81F firewall. All the devices running any iOS other than the 18.3.1 are working fine. just the iPhones and iPads running 18.3.1 are affected, and it is only affecting the email sync with O365, all other traffic is working fine.