Unable to open Email Quarantine portal. It gives an "Invalid Domain" error when you try to login to the quarantine portal.
The domain is not provisioned to the region you are trying to login.
Please make sure which region your domain is provisioned on, US or EU.
If your domain is assigned to US, Email Quarantine portal URL is https://us.quarantine.symantec.com/
If your domain is assigned to EU, Email Quarantine portal URL is https://eu.quarantine.symantec.com/
For example, If your domain is assigned to the US region while you try to login to https://eu.quarantine.symantec.com, you will get the " Invalid Domain " error.