In an attempt to fix another issue with public folder migration, i attempted to install CU3 for exchange 2013. it fails at 90% when it is doing the prerequisite test with an error regarding restarting the WRMSVC service. Everything was working fine yesterday until this update failed and now we are not receiving any mail. I've rebooted the server several times and no change. I'm not sure where to even start. Has anyone else successfully installed CU3? this is a single CAS and mailbox server.