SQL Server 2008 R2 - The request failed or the service did not respond in timely fashion
When the server cannot start, the first thing to consult is SQL Server error log.
There can be different reasons, for example, banally the port assigned is occupied. But in OP case it was 


  The server could not load the certificate it needs to initiate an SSL
  connection


The error message itself suggested what to do: 


  Check certificates to make sure they are valid


Another option in this case was to remove encryption at all if it was configured by mistake