Error code 49

CM_PROB_REGISTRY_TOO_LARGE

Windows cannot start new hardware devices because the system hive is too large (exceeds the Registry Size Limit). (Code 49)
To fix this problem, you should first try uninstalling any hardware devices that you are no longer using. If that doesn't solve the problem, then you will have to reinstall Windows.

Cause

The system hive has exceeded its maximum size and new devices cannot work until the size is reduced. The system hive is a permanent part of the registry associated with a set of files that contains information related to the configuration of the computer on which the operating system is installed.

Solution

Uninstall disconnected devices using health check.

If you still have the same error, uninstall devices you no longer need using device control.