diff --git a/app.py b/app.py
index c669e8e..8d70fcb 100644
--- a/app.py
+++ b/app.py
@@ -17,7 +17,7 @@ from blueprints.data_imports import data_imports_bp
 from blueprints.users import users_bp
 from blueprints.sessions import sessions_bp
 from blueprints.admin_locations import admin_locations_bp
-from blueprints.counting import counting_bp  # Add this import
+from blueprints.counting import counting_bp  
 from utils import login_required
 
 # Register Blueprints
@@ -25,7 +25,7 @@ app.register_blueprint(data_imports_bp)
 app.register_blueprint(users_bp)
 app.register_blueprint(sessions_bp)
 app.register_blueprint(admin_locations_bp)
-app.register_blueprint(counting_bp)          # Add this registration
+app.register_blueprint(counting_bp)          
 
 # V1.0: Use environment variable for production, fallback to demo key for development
 app.secret_key = os.environ.get('SCANLOOK_SECRET_KEY', 'scanlook-demo-key-replace-for-production')
@@ -36,7 +36,7 @@ app.config['PERMANENT_SESSION_LIFETIME'] = timedelta(hours=1)
 
 
 # 1. Define the version
-APP_VERSION = '0.10.0'
+APP_VERSION = '0.11.0'
 
 # 2. Inject it into all templates automatically
 @app.context_processor
diff --git a/blueprints/__pycache__/counting.cpython-313.pyc b/blueprints/__pycache__/counting.cpython-313.pyc
index d337f5f..07feb82 100644
Binary files a/blueprints/__pycache__/counting.cpython-313.pyc and b/blueprints/__pycache__/counting.cpython-313.pyc differ
diff --git a/blueprints/__pycache__/data_imports.cpython-313.pyc b/blueprints/__pycache__/data_imports.cpython-313.pyc
index acb87fb..6575814 100644
Binary files a/blueprints/__pycache__/data_imports.cpython-313.pyc and b/blueprints/__pycache__/data_imports.cpython-313.pyc differ
diff --git a/blueprints/counting.py b/blueprints/counting.py
index 5872f1c..94bb7be 100644
--- a/blueprints/counting.py
+++ b/blueprints/counting.py
@@ -79,6 +79,9 @@ def start_bin_count(session_id):
     if not sess:
         flash('Session not found or archived', 'warning')
         return redirect(url_for('dashboard'))
+    if not sess['master_baseline_timestamp']:
+        flash('Master File not uploaded. Please upload it before starting bins.', 'warning')
+        return redirect(url_for('counting.my_counts', session_id=session_id))
     
     location_name = request.form.get('location_name', '').strip().upper()
     
@@ -144,6 +147,9 @@ def count_location(session_id, location_count_id):
     if not sess:
         flash('Session not found or archived', 'warning')
         return redirect(url_for('dashboard'))
+    if not sess['master_baseline_timestamp']:
+        flash('Master File not uploaded. Please upload it before starting bins.', 'warning')
+        return redirect(url_for('counting.my_counts', session_id=session_id))
     
     location = query_db('''
         SELECT * FROM LocationCounts
diff --git a/blueprints/data_imports.py b/blueprints/data_imports.py
index fcb802f..8ebd24b 100644
--- a/blueprints/data_imports.py
+++ b/blueprints/data_imports.py
@@ -152,4 +152,4 @@ def upload_master(session_id):
     finally:
         conn.close()
 
-    return redirect(url_for('sessions. session_detail', session_id=session_id))
\ No newline at end of file
+    return redirect(url_for('sessions.session_detail', session_id=session_id))
\ No newline at end of file
diff --git a/templates/my_counts.html b/templates/my_counts.html
index 5265fde..e6d2b1a 100644
--- a/templates/my_counts.html
+++ b/templates/my_counts.html
@@ -9,10 +9,19 @@
             <a href="{{ url_for('dashboard') }}" class="breadcrumb">← Back to Dashboard</a>
             <h1 class="page-title">My Active Counts</h1>
             <p class="page-subtitle">{{ count_session.session_name }}</p>
+            {% if not count_session.master_baseline_timestamp %}
+            <p class="page-subtitle">Master File not uploaded yet. Please contact an admin before starting bins.</p>
+            {% endif %}
         </div>
+        {% if count_session.master_baseline_timestamp %}
         <button class="btn btn-primary" onclick="showStartBinModal()">
             <span class="btn-icon">+</span> Start New Bin
         </button>
+        {% else %}
+        <button class="btn btn-primary" disabled title="Upload a Master File to start bins">
+            <span class="btn-icon">+</span> Start New Bin
+        </button>
+        {% endif %}
     </div>
 
     <!-- Active Bins -->