Changing Driver Loading Controls in the Registry

Under most circumstances, you should define the startup behavior of a device or a service by using the Devices option or the Services option in Control Panel, or by using Server Manager under Windows NT Server. Use these methods in specific cases where you cannot define behavior by using the other administrative tools.

You can change the basic value entries in the Registry to control driver loading for a specific driver. For example, you can change:

To change the behavior of a driver or service

1. Select the subkey for the driver or service in the following Registry path:

HKEY_LOCAL_MACHINE\System
\CurrentControlSet
\Services
\DriverName

2. If you want to change how system startup proceeds if the driver is not loaded or the service is not started, change the value of ErrorControl as follows:

Value

Meaning

0x3

Critical. Fail the attempted system startup.

0x2

Severe. Switch to LastKnownGood or, if already using LastKnownGood, continue in case of error.

0x1

Normal. Continue startup if the driver fails to load, but display a message noting the failure.

0x0

Ignore.


3. If you want to change the dependencies for loading the service, specify new values for the DependOnGroup, DependOnService, or Tag value entry.

4. If you want to change when the service is started or the driver is loaded, change the Start value as follows:

Value

Start type

Meaning

0x0

Boot

Loaded by the Boot Loader.

0x1

System

Loaded at Kernel initialization.

0x2

Auto load

Loaded or started automatically at startup.

0x3

Load on demand

Available, but started only by the user.

0x4

Disabled

Do not start.


5. To put these values into effect, close Registry Editor, then shut down and restart the computer.

For details about Start and ErrorControl values, see their definitions in Regentry.hlp, the Registry Help file on the Windows NT Workstation Resource Kit CD.