Sometimes during kernel-mode debugging, the target computer stops responding to the debugger.
These commands frequently restore communication between the host and the target. However, resynchronization might not always be successful, especially if you are using a 1394 kernel connection.
The .restart (Restart Kernel Connection) command provides a more powerful method of resynchronization. This command is equivalent to exiting the debugger and then attaching a new debugger to the existing session. This command is available only in KD, not in WinDbg.
The .restart command is most useful when you are performing remote debugging through remote.exe. (In this kind of debugging, it might be difficult to end and restart the debugger.) However, you cannot use .restart from a debugging client if you are performing remote debugging through the debugger.