Oracle.DataAccess.Client.OracleException: The provider is not compatible with the version of Oracle client

"Oracle.DataAccess.Client.OracleException: The provider is not compatible with the version of Oracle client"

I have 3 different server environment with oracle client 11g installed, in 2 of them application is running correctly , but in one of them the above error is coming while trying to connect to oracle database. Please help me telling the possible solution.

Thanks,

Ritwik