diff --git a/app/auth.py b/app/auth.py
index aaae52a..8c69b5f 100644
--- a/app/auth.py
+++ b/app/auth.py
@@ -11,7 +11,10 @@ def check_token_domain(db_path: str, token: str, domain: str) -> bool:
 
 # Verify user's passowrd for login. Return UserID on success, None on failure
 def user_login(db_path: str, username: str, password: str) -> int | None:
-    userid = db.User.get_id(db_path, username)
+    try:
+        userid = db.User.get_id(db_path, username)
+    except ValueError:
+        return None
 
     pwsalt, pwhash = db.User.get_password_hash(db_path, userid)
 
diff --git a/app/db.py b/app/db.py
index 17d4080..2b094d4 100644
--- a/app/db.py
+++ b/app/db.py
@@ -243,6 +243,9 @@ class User:
             for domain in domains:
                 domain = domain.strip()
 
+                if len(domain) < 1:
+                    continue
+
                 cursor.execute('''
                     INSERT INTO Domains (domain, userid) VALUES (?, ?)
                 ''', (domain, userid))
@@ -270,15 +273,15 @@ class User:
         if not User.exists(db_path, userid):
             raise ValueError(f"User {userid} does not exist")
 
-        if not token_name.isalnum():
-            raise ValueError("Token name has to be alphanumeric")
-
         if len(token_name) < 1:
             raise ValueError("Token name has to be at least 1 character long")
 
         if len(token_name) > 16:
             raise ValueError("Token name has to be at most 16 characters long")
 
+        if not token_name.isalnum():
+            raise ValueError("Token name has to be alphanumeric")
+
         token_name_list = User.get_token_names(db_path, userid)
 
         if len(token_name_list) >= 5:
diff --git a/app/main.py b/app/main.py
index 698f836..a0e4299 100644
--- a/app/main.py
+++ b/app/main.py
@@ -49,19 +49,15 @@ def homepage():
 # Handle login
 @app.route('/login', methods=["POST"])
 def login():
-    if "user" not in request.form or "pass" not in request.form:
-        return redirect("/"), 400
+    userid = auth.user_login(DB_PATH, request.form.get("user"), request.form.get("pass"))
 
-    if request.form["user"].strip() == "" or request.form["pass"].strip() == "":
-        return redirect("/"), 400
-
-    userid = auth.user_login(DB_PATH, request.form["user"], request.form["pass"])
     if userid is None:
+        flash("Invalid user or password")
         return redirect("/")
 
     session["USERID"] = userid
 
-    return redirect("/dashboard", code=302)
+    return redirect("/dashboard")
 
 
 # Log out by clearing session data
@@ -76,7 +72,9 @@ def logout():
 def dashboard():
     if session.get("USERID") is None:
         return redirect("/")
+
     userid = session.get("USERID")
+
     username = db.User.get_username(DB_PATH, userid)
     domains = db.User.get_domains(DB_PATH, userid)
     tokens = db.User.get_token_names(DB_PATH, userid)
@@ -96,11 +94,14 @@ def generate_token():
         return redirect("/")
 
     if "token" not in request.form:
-        return redirect("/dashboard")
-    if request.form["token"].strip() == "":
+        flash("Token name not supplied")
         return redirect("/dashboard")
 
-    token = db.User.generate_token(DB_PATH, session.get("USERID"), request.form["token"])
+    try:
+        token = db.User.generate_token(DB_PATH, session.get("USERID"), request.form["token"])
+    except ValueError as e:
+        flash(str(e))
+        token = None
 
     if token is not None:
         flash(token)
@@ -115,11 +116,13 @@ def revoke_token():
         return redirect("/")
 
     if "token" not in request.form:
-        return redirect("/dashboard")
-    if request.form["token"].strip() == "":
+        flash("Token name not supplied")
         return redirect("/dashboard")
 
-    db.User.revoke_token(DB_PATH, session.get("USERID"), request.form["token"])
+    try:
+        db.User.revoke_token(DB_PATH, session.get("USERID"), request.form["token"])
+    except ValueError as e:
+        flash(str(e))
 
     return redirect("/dashboard")
 
@@ -133,6 +136,7 @@ def create_user():
         return redirect("/dashboard")
 
     if 'username' not in request.form or 'password' not in request.form:
+        flash('Required fields not supplied')
         return redirect("/dashboard")
 
     username = request.form.get("username").strip()
@@ -147,9 +151,21 @@ def create_user():
         domains = collapse_exp.sub(' ', domains.strip())
         domains = domains.split(" ")
 
-    is_admin = request.form.get("is_admin") is not None
+    is_admin = request.form.get("is_admin")
+    if is_admin is not None:
+        is_admin = is_admin == "true"
+    else:
+        is_admin = False
 
-    flash(db.User.new(DB_PATH, username, password, domains, is_admin, request.form.get('email')))
+    email = request.form.get("email")
+    if email is not None:
+        if email == "":
+            email = None
+
+    try:
+        db.User.new(DB_PATH, username, password, domains, is_admin, email)
+    except ValueError as e:
+        flash(str(e))
 
     return redirect("/dashboard")
 
@@ -164,10 +180,11 @@ def update_user():
 
     userid = request.form.get("userid")
     if userid is None:
+        flash("UserID not supplied")
         return redirect("/dashboard")
-    try:
-        userid = int(userid)
-    except ValueError:
+
+    if not db.User.exists(DB_PATH, userid):
+        flash("User does not exist")
         return redirect("/dashboard")
 
     domains = request.form.get('domains')
@@ -175,11 +192,17 @@ def update_user():
         collapse_exp = re.compile(r'\s+')
         domains = collapse_exp.sub(' ', domains.strip())
         domains = domains.split(" ")
-        db.User.set_domains(DB_PATH, userid, domains)
+        try:
+            db.User.set_domains(DB_PATH, userid, domains)
+        except ValueError as e:
+            flash(str(e))
 
     password = request.form.get("password")
     if password is not None:
-        db.User.set_password(DB_PATH, userid, password)
+        try:
+            db.User.set_password(DB_PATH, userid, password)
+        except ValueError as e:
+            flash(str(e))
 
     is_admin = request.form.get("is_admin")
     if is_admin is not None:
@@ -206,9 +229,9 @@ def delete_user():
     userid = request.form.get("userid")
     if userid is None:
         return redirect("/dashboard")
-    try:
-        userid = int(userid)
-    except ValueError:
+
+    if db.User.exists(DB_PATH, userid):
+        flash("User does not exst")
         return redirect("/dashboard")
 
     db.User.delete(DB_PATH, userid)
@@ -223,17 +246,15 @@ def change_password():
         return redirect("/")
 
     if "pass" not in request.form or "pass-new" not in request.form or "pass-rep" not in request.form:
-        flash("password change failed")
-        return redirect("/dashboard")
-    if request.form["pass"] == "" or request.form["pass-new"] == "" or request.form["pass-rep"] == "":
-        flash("password change failed")
+        flash("Required values not supplied")
         return redirect("/dashboard")
 
     oldpass = request.form["pass"]
     newpass = request.form["pass-new"]
+    reppass = request.form["pass-rep"]
 
-    if newpass != request.form["pass-rep"]:
-        flash("passwords do not match")
+    if newpass != reppass:
+        flash("Passwords do not match")
         return redirect("/dashboard")
 
     try:
@@ -242,7 +263,7 @@ def change_password():
         flash(str(e))
         return redirect("/dashboard")
 
-    flash("password changed successfully")
+    flash("Password changed successfully")
     return redirect("/dashboard")
 
 
@@ -262,10 +283,10 @@ def update_addr():
 
         if 'ip' not in request.args:
             ip = request.remote_addr
-        elif not validate_ip(request.args['ip']):
-            return jsonify({"status": "400", "code": "ip-error", "comment": "Invalid IP"}), 400
-        else:
+        elif validate_ip(request.args['ip']):
             ip = request.args['ip']
+        else:
+            return jsonify({"status": "400", "code": "ip-error", "comment": "Invalid IP"}), 400
 
         if 'token' not in request.args:
             return jsonify({"status": "400", "code": "token-error", "comment": "Missing or invalid token"}), 400
diff --git a/app/templates/admin.html b/app/templates/admin.html
index f2c3d91..50affcd 100644
--- a/app/templates/admin.html
+++ b/app/templates/admin.html
@@ -36,7 +36,7 @@
 				</form></td>
 				<td><form method="POST" action="/update-user">
 					<input type="hidden" name="userid" value="{{ user["userid"] }}" />
-					<input type="email" name="email" placeholder="email" value="{{ user["email"] }}"/>
+					<input type="email" name="email" placeholder="email" value="{{ user["email"] if user["email"] }}"/>
 					<button type="submit">update email</button>
 				</form></td>
 				<td><form method="POST" action="/delete-user">
diff --git a/app/templates/index.html b/app/templates/index.html
index ee06efc..4b1010c 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -6,6 +6,14 @@
 <body>
 	<p>Dynamic DNS service for <span style="font-family: monospace">.izbi</span> domains <span style="font-family: monospace">:3</span></p>
 
+{% with messages = get_flashed_messages()%}
+{% if messages%}
+{% for message in messages%}
+        <h3>{{message}}</h3>
+{%endfor%}
+{%endif%}
+{%endwith%}
+
 	<form method="POST" action="/login">
 		<input type="text" name="user" placeholder="username" required autofocus /><br />
 		<input type="password" name="pass" placeholder="password" required /><br />