یک فاجعه بزرگ

من بر روی سرور سایتم رو نصب کردم و دیتا بیس رواتصال دادم بعد هنگام راه اندازی این مشکل بزرگ رو مواجه می شوم
Server Error in '/' Application.
Login failed for user 'mashhadmitdb'.
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: Login failed for user 'mashhadmitdb'.

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): Login failed for user 'mashhadmitdb'.]
System.Data.ProviderBase.DbConnectionPool.GetConne ction(DbConnection owningObject) +437
System.Data.ProviderBase.DbConnectionFactory.GetCo nnection(DbConnection owningConnection) +82
System.Data.ProviderBase.DbConnectionClosed.OpenCo nnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +105
System.Data.SqlClient.SqlConnection.Open() +111
University.Index.Page_Load(Object sender, EventArgs e) +787
System.Web.Util.CalliHelper.EventArgFunctionCaller (IntPtr fp, Object o, Object t, EventArgs e) +15
System.Web.Util.CalliEventHandlerDelegateProxy.Cal lback(Object sender, EventArgs e) +34
System.Web.UI.Control.OnLoad(EventArgs e) +99
System.Web.UI.Control.LoadRecursive() +47
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061


Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET Version:2.0.50727.210

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