Aaaaarg. Why does Oracle make this so confusing!
I have a web appication that was working fine connecting to oracle using
System.Data.OracleClient.
I attempted to install a new version of the oracle client tools (10g) to get
a later version of the odbc drivers. I then uninstalled this version and reverted
to the 9i version.
Since then - my web application no longer works and gives me the 'ol TNS error.
I have tracked down all instances of tnsnames.ora and made sure they are the same.
I have successfully connected to the oracle database via odbc from within the web app,
tnsping resolves appropriately.
toad connects using the tns with no problem
It appears the error is caused when attempting to use the System.Data.OracleClient
as the provider.
The reference to this is: C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Data.OracleClient.dll
Thanks..
Tom