diff --git a/Course3/Lab4/validations.py b/Course3/Lab4/validations.py
old mode 100644
new mode 100755
index b18de65a2e..4ca5b79311
--- a/Course3/Lab4/validations.py
+++ b/Course3/Lab4/validations.py
@@ -13,7 +13,10 @@ def validate_user(username, minlen):
     if len(username) < minlen:
         return False
     # Usernames can only use letters, numbers, dots and underscores
-    if not re.match('^[a-z0-9._]*$', username):
+
+    if re.match('^[._]', username):
+        return False
+    elif not re.match('^[a-z0-9._]*$', username):
         return False
     # Usernames can't begin with a number
     if username[0].isnumeric():
@@ -22,3 +25,11 @@ def validate_user(username, minlen):
 
 
 
+print(validate_user("blue.kale", 3)) # True
+
+print(validate_user(".blue.kale", 3)) # Currently True, should be False
+
+print(validate_user("red_quinoa", 4)) # True
+
+print(validate_user("_red_quinoa", 4)) # Currently True, should be False
+