asp.net, SQL, IIS - User does not have permission to perform this action

I have an asp.net site that works fine when debugging in visual studio.
When I publish the site and try browsing to it, I get:


Server Error in '/app1' Application.
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User does not have permission to perform this action.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: User does not have permission to perform this action.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.  

Stack Trace:


[SqlException (0x80131904): User does not have permission to perform this action.]
   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +5009598
   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning() +234
   System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2275
   System.Data.SqlClient.SqlInternalConnectionTds.CompleteLogin(Boolean enlistOK) +35
   System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, SqlConnection owningObject) +183
   System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, TimeoutTimer timeout) +239
   System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, TimeoutTimer timeout, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +195
   System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +232
   System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +5023255
   System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +33
   System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +524
   System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66
   System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +479
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +108
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +126
   System.Data.SqlClient.SqlConnection.Open() +125
   System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context, Boolean revertImpersonate) +95
   System.Web.DataAccess.SqlConnectionHelper.GetConnection(String connectionString, Boolean revertImpersonation) +206
   System.Web.Security.SqlMembershipProvider.GetPasswordWithFormat(String username, Boolean updateLastLoginActivityDate, Int32& status, String& password, Int32& passwordFormat, String& passwordSalt, Int32& failedPasswordAttemptCount, Int32& failedPasswordAnswerAttemptCount, Boolean& isApproved, DateTime& lastLoginDate, DateTime& lastActivityDate) +827
   System.Web.Security.SqlMembershipProvider.CheckPassword(String username, String password, Boolean updateLastLoginActivityDate, Boolean failIfNotApproved, String& salt, Int32& passwordFormat) +105
   System.Web.Security.SqlMembershipProvider.ValidateUser(String username, String password) +106
   System.Web.UI.WebControls.Login.AuthenticateUsingMembershipProvider(AuthenticateEventArgs e) +60
   System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs e) +129
   System.Web.UI.WebControls.Login.AttemptLogin() +127
   System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +101
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37
   System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +125
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +167
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5563

 


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Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1