ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

오라클을 사용하는 ASP.NET 서비스 중에 다음과 같은 오류가 발생한다면?

Server Error in '/' Application.
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ORA-12514: TNS:listener does not currently know of service requested in connect descriptor 
  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: Oracle.DataAccess.Client.OracleException: ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

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: 

[OracleException (0x80004005): ORA-12514: TNS:listener does not currently know of service requested in connect descriptor]
   Oracle.DataAccess.Client.OracleException.HandleErrorHelper(Int32 errCode, OracleConnection conn, IntPtr opsErrCtx, OpoSqlValCtx* pOpoSqlValCtx, Object src, String procedure, Boolean bCheck) +1921
   Oracle.DataAccess.Client.OracleException.HandleError(Int32 errCode, OracleConnection conn, IntPtr opsErrCtx, Object src) +88
   Oracle.DataAccess.Client.OracleConnection.Open() +10098
   WebSiteTest.odpnet20test.Page_Load(Object sender, EventArgs e) in d:\...\WebSiteTest4\odpnet20test.aspx.cs:181
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +25
   System.Web.UI.Control.LoadRecursive() +116
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2830

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Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272