Email, Spam Control, Checking if domain is blocked by Spam Control

How do I find if a domain is blocked from sending to @illinois.edu?

Our spam control engine uses a domain's reputation score to determine if that domain is a spammer. You can check the domain and/or the IP of the sending server using one of the following reputation services:
If you're not familiar with the 'nslookup' command, you can use http://www.kloth.net/services/nslookup.php to get its IP. Enter the domain name and click [Look it up] to get the IP address, then paste into the Proofpoint URL above. If you feel the domain is blocked in error (false positive) then send an email to consult@illinois.edu and a service administrator from our team will look into the matter and get back to you.

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