We are having the autodiscover popup show up on several different mailboxes asking to allow settings from a domain that is not ours (specifically grubhub)
Allow this website to configure email@example.com server settings?
Your account was redirected to this website for settings.
You should only allow settings from sources you know and trust.
We are not grubhub.
Why would it be asking for grubhub.com autodiscover when we are not gruhub?