If I restart the server gracefully (via OS or vSphere) then server manager does not start, you can't run any mmc, sql does not start, application services do not start. This is since applying a patch to the critical dotnet application that effectively removes the 32-bit version and installs a 64-bit version. This was Sandboxed and tested OK. If I abrupt power off the server and it recovers from a dirty shutdown then all applications and services start OK. This is a 2012-R2 server running a critical application with an SQL back-end that is very expensive to migrate to a fresh installation. On the other hand if it's half broken and I proceed to just run every tool I can think of just keep buttoning it off I run the possibility of it not working at all and then I have a whole department not working and we would be waiting for availability of a consultant to migrate /rebuild on a new server. If I sanbox the server (+plus DC + client etc) then I cannot recreate the problem.