Hello Manuel,
I have the same problem, but one version higher, as we are using MSSQL Server 2014:
Error: The driver release (11) is lower than the server release (12)
and all the WP are dying... According to Microsoft, there is no Native client 12 !!!!!!!!!
What to do now ???
It says "There is no SQL Server 2014 Native Client". I am sorry, but I can't post the link, as for some strange reason, copy-paste is not working :-(