Not able to whitelist a subnet x.x.x.0/23 in O365 connector. I have set up a connector to allow devices to send email using O365 but somehow the connector only allows /24 - /32. Is it possible to work around this.

Not able to whitelist a subnet x.x.x.0/23 in O365 connector. I have set up a connector to allow devices to send email using O365 but somehow the connector only allows /24 - /32. Is it possible to work around this.

Not possible by design.
Use a transport rule instead:
https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/configure-the-connection-filter-policy?view=o365-worldwide#skip-spam-filtering-for-a-cidr-ip-outside-of-the-available-range
AndyDavid.
Thanks for your response. I have added the IP range to Bypass the Spam Filter but on the device they are still getting the error that connection to the email server failed. I added the individual printer IP addresses to the mail relay on Exchange on prem and they are able to send email but it fails when I use O365. The host name I am using is the O365 MX record domainxx-com01e.mail.protection.outlook.com
Did you create a transport rule? IF so, what does it look like?
According to the recommended Microsoft doc, I created a rule to bypass spam filter and added sender IP addresses (xx.xx.xx.0/23), set the SCL to Bypass spam filtering and mode of the rule is enforced.

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