c# - Sections must only appear once per config file. See the help topic for exceptions -

there problem selected data store. can caused invalid server name or credentials, or insufficient permission. can caused role manager feature not being enabled. click button below redirected page can choose new data store.

the following message may in diagnosing problem: sections must appear once per config file. see topic exceptions. (c:\users\berkay.bektas\desktop\x\yalcomania_project\yalcomania_app\yalcomaniatours\yalcomaniatours.ui.webapp\web.config line 20)

    <?xml version="1.0"?> <!--   more information on how configure asp.net application, please visit   http://go.microsoft.com/fwlink/?linkid=169433   --> <configuration>   <configsections>     <!-- more information on entity framework configuration, visit http://go.microsoft.com/fwlink/?linkid=237468 -->     <section name="entityframework" type="system.data.entity.internal.configfile.entityframeworksection, entityframework, version=6.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089" requirepermission="false"/>   </configsections>   <system.web>     <rolemanager enabled="true" />     <membership>       <providers>         <clear/>         <add name="aspnetsqlmembershipprovider" type="system.web.security.sqlmembershipprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a" connectionstringname="membershipconn" enablepasswordretrieval="false" enablepasswordreset="true" requiresquestionandanswer="true" applicationname="/" requiresuniqueemail="false" passwordformat="hashed" maxinvalidpasswordattempts="5" minrequiredpasswordlength="7" minrequirednonalphanumericcharacters="1" passwordattemptwindow="10" passwordstrengthregularexpression=""/>       </providers>     </membership>      <rolemanager>       <providers>         <clear/>         <add name="aspnetsqlroleprovider" connectionstringname="membershipconn" applicationname="/" type="system.web.security.sqlroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>         <add name="aspnetwindowstokenroleprovider" applicationname="/" type="system.web.security.windowstokenroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>       </providers>     </rolemanager>       <compilation debug="true" targetframework="4.5">       <assemblies>         <add assembly="system.web.dynamicdata, version=4.0.0.0, culture=neutral, publickeytoken=31bf3856ad364e35"/>         <add assembly="system.core, version=4.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>         <add assembly="system.componentmodel.dataannotations, version=4.0.0.0, culture=neutral, publickeytoken=31bf3856ad364e35"/>         <add assembly="system.data.linq, version=4.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>         <add assembly="system.data.entity, version=4.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>         <add assembly="system.web.entity, version=4.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>         <add assembly="system.xml.linq, version=4.0.0.0, culture=neutral, publickeytoken=b77a5c561934e089"/>       </assemblies>     </compilation>     <httpruntime targetframework="4.5"/>    </system.web>   <entityframework>     <defaultconnectionfactory type="system.data.entity.infrastructure.localdbconnectionfactory, entityframework">       <parameters>         <parameter value="v11.0"/>       </parameters>     </defaultconnectionfactory>     <providers>       <provider invariantname="system.data.sqlclient" type="system.data.entity.sqlserver.sqlproviderservices, entityframework.sqlserver"/>     </providers>   </entityframework>   <connectionstrings>     <add name="membershipconn" connectionstring="server=.;database=yalcomania;user id=sa;password=123"/>     <add name="yalcomaniaentities" connectionstring="metadata=res://*/model1.csdl|res://*/model1.ssdl|res://*/model1.msl;provider=system.data.sqlclient;provider connection string=&quot;data source=.;initial catalog=yalcomania;user id=sa;password=123;multipleactiveresultsets=true;app=entityframework&quot;" providername="system.data.entityclient"/>   </connectionstrings>   <appsettings>        <add key="validationsettings:unobtrusivevalidationmode" value="none"/>    </appsettings> </configuration> 

going guess has due with:

<rolemanager enabled="true" /> 

and

<rolemanager>   <providers>     <clear/>     <add name="aspnetsqlroleprovider" connectionstringname="membershipconn" applicationname="/" type="system.web.security.sqlroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>     <add name="aspnetwindowstokenroleprovider" applicationname="/" type="system.web.security.windowstokenroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>   </providers> </rolemanager> 

note error message "sections must appear once..." have 2 rolemanager sections. try combine such:

<rolemanager enabled="true">   <providers>     <clear/>     <add name="aspnetsqlroleprovider" connectionstringname="membershipconn" applicationname="/" type="system.web.security.sqlroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>     <add name="aspnetwindowstokenroleprovider" applicationname="/" type="system.web.security.windowstokenroleprovider, system.web, version=4.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a"/>   </providers> </rolemanager> 

additionally, i'd imagine want provide defaultprovider within rolemanager section.