is there any problem to install different oracle 11g versions. I mean if I have installed oracle 11.1.0.6 and i do install oracle 11.1.0.7 will anything conflict, such as oracle_home path, or any registry keys? will it cause any problem to .Net references to Oracle dlls?
On unix this is no problem at all, using oraenv effectively selects the ORACLE_HOME that you want to use in your PATH. On windows, the installer adds the latest installed ORACLE_HOME\bin to the PATH variable. It should cause no problems when all applications use the registry in the correct way.
Ronald.
1.3.5 Multiple Oracle Home Support
Oracle Database supports multiple Oracle homes. This means that you can install this release or previous releases of the software more than once on the same system, in different Oracle home directories. This allows flexibility in deployment and maintenance of the database software. For example, it allows you to run different versions of the database simultaneously on the same system, or it allows you to upgrade specific database or Automatic Storage Management instances on a system without affecting other running databases. However, when you have installed multiple Oracle Homes on a single system, there is also some added complexity introduced that you may need to take into account to allow these Oracle Homes to coexist.