After I installed .net v4.5 i ran into the following problem:
A connection was successfully established with the server, but then an error occurred during the pre-login handshake. (provider: SSL Provider, error: 0 - The wait operation timed out.)
The funny thing was that the error only occured when connecting to a remote SQL server. The bug is reported on Microsoft Connect.
The work around for me was to remove non-IFS LSP installed Winsock Catalog Provider as described in the KB 2568167.