I have installed 64-bit Oracle 11g on my development machine to work on some samples using Entity Framework 4.1 (a.k.a. “code first”). If you ask me why I installed 64-bit version and not 32-bit, I will not answer. I don’t know. Perhaps because Oracle has always associated for me with something big and 64 bits are certainly greater than 32. Now I think it was a mistake, but on the other hand it made me explore something new.
An attempt to connect to the database failed with the following error message: “ —-> System.Exception : Unable to load D:\Oracle\Vagif\product\11.2.0\dbhome_1\bin\oci.dll. Please check that you use 32x version of Oracle client with 32x application.” I checked project platform target. “Any CPU”. I was using TestDriven.NET test runner.
I’ve changed build platform to “64x” and tests passed. I also ran tests built for “Any CPU” using 64-bit NUnit runner, and they passed too. What I wanted now is leave “Any CPU” option for all projects and be able to test them from within Visual Studio.
Resharper was the only once that worked like a charm, no matter what I did. It uses 64-bit task runner on 64-bit platforms, so it just works.
Although TestDriven.NET test runner failed initially, it was easy to re-configure it: just choose 64-bit option for the test runner in its settings page.
The only bad guy was built-in Visual Studio test runner: it runs only as 32-bit process, so without unsupported patching it as 64-bit process (described here ) it can’t run tests in 64-bit mode.
UPDATE. I stand corrected. MsTest also supports 64-bit mode.