diff --git a/backend/mpc-system/scripts/deploy.sh b/backend/mpc-system/scripts/deploy.sh
index b4407242..b3995d4b 100644
--- a/backend/mpc-system/scripts/deploy.sh
+++ b/backend/mpc-system/scripts/deploy.sh
@@ -145,23 +145,42 @@ setup_directories() {
 configure_postgres() {
     log_info "Configuring PostgreSQL..."
 
-    # Load environment variables
+    # Load environment variables - use MPC_ prefix variables (same as Go code uses)
     source "$CONFIG_DIR/mpc.env" 2>/dev/null || true
 
-    local DB_USER="${POSTGRES_USER:-mpc_user}"
-    local DB_PASS="${POSTGRES_PASSWORD:-mpc_secret_password}"
-    local DB_NAME="mpc_system"
+    local DB_USER="${MPC_DATABASE_USER:-mpc_user}"
+    local DB_PASS="${MPC_DATABASE_PASSWORD:-your_secure_postgres_password_here}"
+    local DB_NAME="${MPC_DATABASE_DBNAME:-mpc_system}"
+
+    # Configure pg_hba.conf to allow password authentication for local connections
+    local PG_HBA="/etc/postgresql/*/main/pg_hba.conf"
+    for hba_file in $PG_HBA; do
+        if [ -f "$hba_file" ]; then
+            # Backup original
+            cp "$hba_file" "${hba_file}.bak" 2>/dev/null || true
+            # Change 'peer' to 'md5' for local connections to allow password auth
+            sed -i 's/local   all             all                                     peer/local   all             all                                     md5/' "$hba_file"
+            sed -i 's/host    all             all             127.0.0.1\/32            scram-sha-256/host    all             all             127.0.0.1\/32            md5/' "$hba_file"
+            sed -i 's/host    all             all             ::1\/128                 scram-sha-256/host    all             all             ::1\/128                 md5/' "$hba_file"
+            log_info "Updated pg_hba.conf at $hba_file"
+        fi
+    done
+
+    # Reload PostgreSQL to apply pg_hba.conf changes
+    systemctl reload postgresql 2>/dev/null || systemctl restart postgresql
 
     # Create database and user
-    sudo -u postgres psql -c "CREATE USER $DB_USER WITH PASSWORD '$DB_PASS';" 2>/dev/null || true
+    sudo -u postgres psql -c "CREATE USER $DB_USER WITH PASSWORD '$DB_PASS';" 2>/dev/null || \
+        sudo -u postgres psql -c "ALTER USER $DB_USER WITH PASSWORD '$DB_PASS';"
     sudo -u postgres psql -c "CREATE DATABASE $DB_NAME OWNER $DB_USER;" 2>/dev/null || true
     sudo -u postgres psql -c "GRANT ALL PRIVILEGES ON DATABASE $DB_NAME TO $DB_USER;" 2>/dev/null || true
+    sudo -u postgres psql -d "$DB_NAME" -c "GRANT ALL ON SCHEMA public TO $DB_USER;" 2>/dev/null || true
 
     # Run migrations
     log_info "Running database migrations..."
-    PGPASSWORD="$DB_PASS" psql -h localhost -U "$DB_USER" -d "$DB_NAME" -f "$MPC_HOME/migrations/001_init_schema.up.sql" 2>/dev/null || log_warn "Migration may have already been applied"
+    PGPASSWORD="$DB_PASS" psql -h 127.0.0.1 -U "$DB_USER" -d "$DB_NAME" -f "$MPC_HOME/migrations/001_init_schema.up.sql" 2>/dev/null || log_warn "Migration may have already been applied"
 
-    log_info "PostgreSQL configured"
+    log_info "PostgreSQL configured with user '$DB_USER' and database '$DB_NAME'"
 }
 
 configure_redis() {
@@ -507,6 +526,22 @@ build() {
     log_info "Start services with: $0 start"
 }
 
+# ============================================
+# Reconfigure Command (fix existing installation)
+# ============================================
+reconfigure() {
+    check_root
+
+    log_info "Reconfiguring MPC-System infrastructure..."
+
+    configure_postgres
+    configure_redis
+    configure_rabbitmq
+
+    log_info "Reconfiguration complete!"
+    log_info "Restart services with: $0 restart"
+}
+
 # ============================================
 # Uninstall Command
 # ============================================
@@ -550,6 +585,9 @@ case "${1:-}" in
     build)
         build
         ;;
+    reconfigure)
+        reconfigure
+        ;;
     start)
         start_services
         ;;
@@ -571,17 +609,18 @@ case "${1:-}" in
     *)
         echo "MPC-System Deployment Script"
         echo ""
-        echo "Usage: $0 {install|build|start|stop|restart|status|logs|uninstall}"
+        echo "Usage: $0 {install|build|reconfigure|start|stop|restart|status|logs|uninstall}"
         echo ""
         echo "Commands:"
-        echo "  install   - Install system dependencies (Go, PostgreSQL, Redis, RabbitMQ)"
-        echo "  build     - Build services and configure infrastructure"
-        echo "  start     - Start all MPC services"
-        echo "  stop      - Stop all MPC services"
-        echo "  restart   - Restart all MPC services"
-        echo "  status    - Show service status"
-        echo "  logs      - View service logs (use: $0 logs [service-name])"
-        echo "  uninstall - Remove MPC services"
+        echo "  install     - Install system dependencies (Go, PostgreSQL, Redis, RabbitMQ)"
+        echo "  build       - Build services and configure infrastructure"
+        echo "  reconfigure - Reconfigure PostgreSQL/Redis/RabbitMQ (fix auth issues)"
+        echo "  start       - Start all MPC services"
+        echo "  stop        - Stop all MPC services"
+        echo "  restart     - Restart all MPC services"
+        echo "  status      - Show service status"
+        echo "  logs        - View service logs (use: $0 logs [service-name])"
+        echo "  uninstall   - Remove MPC services"
         echo ""
         echo "Example:"
         echo "  $0 install       # First time setup"
@@ -590,6 +629,10 @@ case "${1:-}" in
         echo "  $0 start         # Start services"
         echo "  $0 status        # Check status"
         echo ""
+        echo "Troubleshooting:"
+        echo "  $0 reconfigure   # Fix database authentication issues"
+        echo "  $0 restart       # Then restart services"
+        echo ""
         exit 1
         ;;
 esac