Using transaction scope and querying

I'm using entity framework with oracle DB. I tried to use transaction scope (because I want the option to rollback):

using (TransactionScope ts = new TransactionScope())
{
    开发者_高级运维  .....
}

The problem is that when I'm trying to query inside the using statement, an exception is thrown:

Unable to load DLL 'oramts.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)

How can I solve this problem?

The Oramts.dll file is not included as a default installation when you install the Oracle client connectivity software. I think you have to install Oracle Services for Microsoft Transaction Server to use TransactionScope.