Native client for MS SQL is not installed.

I've been trying to install Solution Manager 7.1 on Windows 2008 R2 SP1 MSSQL2012 but i'm facing the following error right after i chose MSSQLSRV in the define parameters phase:

"Native client for MS SQL is not installed". I can see the native clients is installed already in the program lists and can see it in the ODBC Drivers tab as i used the script "SQL4SAP" to install the database and it was finished successfully. Please, provide me with information if you do have any about this issue, thanks. (note: I'm doing a central installation, not sure why native client is needed)