
RichardH.36605 (Customer) asked a question.
Hi,
My company has spam filter which blocks all OKTA one-time password messages + AD sync notifications. They tried using domain *.okta.com but did not work. So what should be the domain to be whitelisted? Alternatively what is the IP addresses of email servers so that they could be used for whitelisting instead?
Thanks.

https://help.okta.com/en/prod/Content/Topics/Security/Firewall_Whitelisting.htm
If they're trying to whitelist an email domain in the spam filter, they should be using "okta.com", not "*.okta.com". The latter would only match Okta subdomains, not the root itself.
Thanks all.
@Mike: I'll try to confirm with them which domain string they used in whitelist.