For some reason the add this website to the zone greyed out for all users on the domain when going into IE options\security. We had a GPO that put our SharePoint site in the zone awhile back but that GPO has been removed and there are no settings in that section of the domain policy anymore. It was in the Site to zone assignment list. I even tried adding the SharePoint URL to the Site to zone assignment list again to see if it would add it that way but its not doing it.
I have tried everything from every post online and don't know if there is anything else I could try to get this not to be greyed out anymore.
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