title: ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
body: <p>We have an ASP.net web-app running in the following environment -</p>
  
  <p><em><strong>Existing Environment</em></strong></p>
  
  <p>Operating System : Windows 2003</p>
  
  <p>Framework : .NET Framework : 2.0</p>
  
  <p>IIS : 6.0</p>
  
  <p>Database : Oracle 10g</p>
  
  <p>We wished to upgrade this to the following environment </p>
  
  <p><em><strong>Present Environment</em></strong> </p>
  
  <p>Operating System : Windows 2008 R2 x64</p>
  
  <p>Framework : .NET Framework : 2.0</p>
  
  <p>IIS : 7.0</p>
  
  <p>Database : Oracle 11g</p>
  
  <p>While doing so, we face the below issue </p>
  
  <p>ODBC Connection Issue on Windows Server 2008 R2 64 bit</p>
  
  <p>ODBC connection could not be established from the ASP.net Web Application in Windows Server 2008 R2.</p>
  
  <p>Application throws an Error :  <strong>ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified.</strong></p>
  
  <p>Connection String : </p>
  
  <pre><code>&lt;add name="ConnectionString" connectionString="Driver=Oracle in XE;Dsn=winerenew;uid=winere;pwd=winere;dbq=XE;dba=W;apa=T;exc=F;fen=T;qto=T;frc=10;fdl=10;lob=T;rst=T;btd=F;bam=IfAllSuccessful;num=NLS;dpm=F;mts=T;mdi=F;csr=F;fwc=F;fbs=64000;tlo=O" providerName="System.Data.Odbc"/&gt;
  </code></pre>
  
  <p>Application works perfectly in windows 2008 x86.</p>
  
  <p>We have tried the following ways to resolve this issue in Windows Server 2008 x64,</p>
  
  <p>1) Enabled the 32-Bit Application in the Application Pool (IIS 7)</p>
  
  <p>2) Executed the ODBC 32 Bit driver with the following command C:\Windows\SysWOW64\odbcad32.exe </p>
  
  <p>3) Installed the oracle 64-bit ODBC driver.</p>
  
  <p>The above methods doesn't seem to  solve this issue. Could anyone tell me the problem behind it and the solution to solve this issue?</p>