Login page issues

I have this problem; I am developing a site with ASP.Net 2005, the database I am using is MySQL and the webserver is Cassini, also I am using forms authentication to handle page access.

I have done tests on all computers accessing the site, however yesterday when I accessed the site from the PC, the login page was presented, but when I click the button to authenticate I stay on the same login page.

I don't know what's going on because I can access the pages on the server, but access from any other terminal it keeps me on the login page without accessing the site (program) itself.

What's wrong here?

This is the login button code

        qfh.User user = qfh.Global.Login(txtUserName.Text, txtPassword.Text, null, null);
        if (user != null)
        {
            // Initialize FormsAuthentication, for what it worth
            FormsAuthentication.Initialize();

            // Create a new ticket used for authentication
            FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(
               1, // Ticket version
               user.UserName, // Username associated with ticket
               DateTime.Now, // Date/time issued
               DateTime.Now.AddMinutes(30), // Date/time to expire
               true, // "true" for a persistent user cookie
               string.Join(",", user.GetRoles()), // User-data, in this case the roles
               FormsAuthentication.FormsCookiePath);// Path cookie valid for

            //Fill the complementary data
            Profile.User = user.UserName;
            Profile.Name = user.Name;
            //Profile.Enterprise = user.Enterprise.EnterpriseCode; // enterprise.EnterpriseCode;
            //Profile.Period = user.Enterprise.GetActivePeriod().PeriodCode; //enterprise.GetActivePeriod().PeriodCode;

            Session["Enterprise"] = user.Enterprise.EnterpriseCode;
            Session["Period"] = user.Enterprise.GetActivePeriod().PeriodCode;

            // Encrypt the cookie using the machine key for secure transport
            string hash = FormsAuthentication.Encrypt(ticket);
            HttpCookie cookie = new HttpCookie(
               FormsAuthentication.FormsCookieName, // Name of auth cookie
               hash); // Hashed ticket

            // Set the cookie expiration time to the tickets expiration time
            if (ticket.IsPersistent) cookie.Expires = ticket.Expiration;

            // Add the cookie to the list for outgoing response
            Response.Cookies.Add(cookie);

            // Redirect to requested URL, or homepage if no previous page
            // requested
            string returnUrl = Request.QueryString["ReturnUrl"];
            if (returnUrl == null) returnUrl = "/";

            // Don't call FormsAuthentication.RedirectFromLoginPage since it
            // could
            // replace the authentication ticket (cookie) we just added
            Response.Redirect(returnUrl);
        }
        else
        {
            lblStatusMessage.Text = Utilities.JSAlert("Access denied");
            return;
        }

      

        
        
        
      

    

This is web.config

<?xml version="1.0"?>
<!-- 
    Note: As an alternative to hand editing this file you can use the 
    web admin tool to configure settings for your application. Use
    the Website->Asp.Net Configuration option in Visual Studio.
    A full list of settings and comments can be found in 
    machine.config.comments usually located in 
    \Windows\Microsoft.Net\Framework\v2.x\Config 
-->
<configuration>

  <configSections>
    <section name="activerecord" type="Castle.ActiveRecord.Framework.Config.ActiveRecordSectionHandler, Castle.ActiveRecord"/>
  </configSections>

  <appSettings>
    <add key="QFH" value="QFH2009" />
  </appSettings>

  <activerecord isWeb="true">
    <config>
      <add key="hibernate.connection.driver_class" value="NHibernate.Driver.MySqlDataDriver"/>
      <add key="hibernate.dialect" value="NHibernate.Dialect.MySQLDialect"/>
      <add key="hibernate.connection.provider" value="NHibernate.Connection.DriverConnectionProvider"/>
      <add key="hibernate.connection.connection_string" value="Server=localhost;Database=qfh;User ID=root;Password=admin;Pooling=false;Min Pool Size=5;Max Pool Size=100;"/>
    </config>
  </activerecord>

  <connectionStrings>
    <!--<add name="QFHConnectionString" connectionString="Dsn=QFH" providerName="System.Data.Odbc"/>-->
    <add name="QFHConnectionString" connectionString="Server=localhost;Database=qfh;User ID=root;Password=admin;Pooling=false;Min Pool Size=5;Max Pool Size=100;"/>
  </connectionStrings>

  <system.web>

    <roleManager defaultProvider="MySqlRoleProvider"
        enabled="true"
        cacheRolesInCookie="true"
        cookieName=".ASPROLES"
        cookieTimeout="30"
        cookiePath="/"
        cookieRequireSSL="false"
        cookieSlidingExpiration="true"
        cookieProtection="All" >

      <providers>
        <clear />
        <add
            name="MySqlRoleProvider"
            type="Andri.Web.MySqlRoleProvider"
            connectionStringName="QFHConnectionString"
            applicationName="QFH"
            writeExceptionsToEventLog="true"
        />
      </providers>

    </roleManager>

    <membership defaultProvider="MySqlMembershipProvider" userIsOnlineTimeWindow="15">

      <providers>
        <clear />
        <add
            name="MySqlMembershipProvider"
            type="Andri.Web.MySqlMembershipProvider"
            connectionStringName="QFHConnectionString"
            applicationName="QFH"
            enablePasswordRetrieval="false"
            enablePasswordReset="true"
            requiresQuestionAndAnswer="true"
            requiresUniqueEmail="true"
            passwordFormat="Hashed"
            writeExceptionsToEventLog="true"
            />
      </providers>

    </membership>

    <!-- 
            Set compilation debug="true" to insert debugging 
            symbols into the compiled page. Because this 
            affects performance, set this value to true only 
            during development.

        -->

    <httpModules>
      <add name="ar.sessionscope" type="Castle.ActiveRecord.Framework.SessionScopeWebModule, Castle.ActiveRecord"/>
    </httpModules>

    <compilation debug="true">
      <assemblies>
        <add assembly="MySql.Data, Version=5.1.7.0, Culture=neutral, PublicKeyToken=C5687FC88969C44D"/>
        <add assembly="System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
        <add assembly="System.Transactions, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="Microsoft.VisualBasic, Version=8.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
      </assemblies>
    </compilation>

    <!--
            The <authentication> section enables configuration 
            of the security authentication mode used by 
            ASP.NET to identify an incoming user. 
        -->
    <!--<roleManager enabled="false"/>-->

    <authentication mode="Forms">
      <forms name="QFHWEBAPP.ASPXAUTH" loginUrl="Login.aspx" defaultUrl="Default.aspx" />
    </authentication>

    <authorization>
      <!-- Do not allow all users come in -->
      <deny users="?"/>
    </authorization>

    <anonymousIdentification enabled="true"/>

    <!-- Temporary fields for the session -->
    <profile defaultProvider="MySQLProfileProvider">
      <providers>
        <!--<add name="MySqlProfileProvider"
     type="Malachi.MySqlProviders.MySqlProfileProvider"-->
        <add name="MySQLProfileProvider"
             type="Ezim.MySql.Web.Profile.MySqlProfileProvider"
             connectionStringName="QFHConnectionString"
             applicationName="QFH"/>
      </providers>
      <properties>
        <add name="User" allowAnonymous="true" type="System.String"/>
        <add name="Name" allowAnonymous="true" type="System.String"/>
        <add name="Period" allowAnonymous="true" type="System.Int32"/>
        <add name="Enterprise" allowAnonymous="true" type="System.Int32"/>
      </properties>
    </profile>
    <!--
            The <customErrors> section enables configuration 
            of what to do if/when an unhandled error occurs 
            during the execution of a request. Specifically, 
            it enables developers to configure html error pages 
            to be displayed in place of a error stack trace.

        <customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm">
            <error statusCode="403" redirect="NoAccess.htm" />
            <error statusCode="404" redirect="FileNotFound.htm" />
        </customErrors>
        -->
    <customErrors mode="Off" />
  </system.web>

  <!--This code is used to make available the css-->
  <location path="css">
    <system.web>
      <authorization>
        <allow users="*"/>
      </authorization>
    </system.web>
  </location>
</configuration>