Thank you for your reply, does it have to be implemented any special place in the web.config? Now I get an IIS error: "The configuration section 'membership' cannot be read because it is missing a section declaration".
I first tried for your code, then this(web.config):
<?xml version="1.0" encoding="UTF-8"?><configuration><connectionStrings><clear/><remove name="StarterSite"/><add name="StarterSite" connectionString="Data Source=saffron.arvixe.com;Initial Catalog=StarterSite;User Id=root;Password=***" providerName="System.Data.SqlClient"/></connectionStrings><system.webServer><directoryBrowse enabled="false" /><defaultDocument><files><clear /><add value="Default.htm" /><add value="Default.asp" /><add value="index.htm" /><add value="index.html" /><add value="iisstart.htm" /><add value="default.aspx" /><add value="default.cshtml" /></files></defaultDocument></system.webServer><system.web><customErrors mode="Off" /></system.web><membership><providers><add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider, System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" connectionStringName="StarterSite" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" applicationName="/" requiresUniqueEmail="false" passwordFormat="Hashed" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="7" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="10" passwordStrengthRegularExpression=""/><add name="MySQLMembershipProvider" type="MySql.Web.Security.MySQLMembershipProvider, MySql.Web, Version=6.3.4.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" connectionStringName="StarterSite" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" applicationName="/" requiresUniqueEmail="false" passwordFormat="Clear" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="7" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="10" passwordStrengthRegularExpression=""/></providers></configuration>