diff --git a/lib/domains/blacklist.txt b/lib/domains/blacklist.txt
index 14075eb7e3..13ed5e05c6 100644
--- a/lib/domains/blacklist.txt
+++ b/lib/domains/blacklist.txt
@@ -87,4 +87,5 @@ student.rockvalleycollege.edu
 sekuco.org
 shitac.tech
 stumail.sdut.edu.cn
-cougarmail.collin.edu
\ No newline at end of file
+cougarmail.collin.edu
+cet.edu
\ No newline at end of file