Login fail for user. Connection string problem for SQL2005

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <!--   User application and configured property settings go here.-->
    <!--   Example: <add key="settingName" value="settingValue"/> -->
    <add key="SqlConnectionString" value="server=ULULALBAB-PC\SQLEXPRESS;persist security info=true;database =SMS2;user=emi;password=database;connect Timeout=5"/>
  </appSettings>
</configuration>