Beware! Make sure you have a backup of the registry and are 100% confident of the syntax of the entries before you change anything. If you mess up, your NT system may never boot again, and you will have to reinstall NT. Try to tweak the registry indirectly whenever you can through control panel/services, system policy editor, and other such utilities.
The behavior of different services can be determined from the value of various subkeys in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\.
ErrorControlREG_DWORDError constant
Error constant values:
- 0x3 Critical error. The attempted system startup fails. If not already using LastKnownGood control set, then switch to LastKnownGood. If already using LastKnownGood control set, then run a bug-check.
- 0x2 Severe error. If not already using LastKnownGood control set, then switch to LastKnownGood. If already using LastKnownGood control set, continue loading OS with error state.
- 0x1 Normal error. If driver doesn’t load correctly, OS will continue loading, but will display warning.
- 0x0 Ignore error. If driver doesn’t load correctly, OS will continue loading, but will not display warning.
GroupREG_DWORDGroup name
Group name value:
Specifies what group the service is a member of. Default is null.
DependOnGroupREG_DWORDGroup name
Group name value:
Specifies that at least one other member from the group must start first before loading this service. Default is empty.
DependOnServiceREG_DWORDService name
Service name value:
Specifies which service(s) must start before this service starts. Default is empty.
ImagePathREG_DWORDPath or filename
Path or filename value:
Specifies a path for the driver or service. Default for a driver is systemroot\system32\drivers\drivername.sys. Default for a service is systemroot\system32\servicename.exe.
TypeREG_DWORDType constant
Type constant values:
- 0x1: Kernel device driver.
- 0x2: Both a file system driver and a kernel device driver.
- 0x4: Set of arguments for an adapter.
- 0x10: Win32 program that is started by the Service Controller and runs as a stand-alone process.
- 0x20: A Win32 service that can share a process with other Win32 services.
ObjectNameREG_DWORDObject name
Object name value:
If type is a Win32 service, this is the account name the service will use to log on. If type is a kernel or file system driver, this is the driver object name that the I/O manager uses to reference the driver.
StartREG_DWORDStart constant
Start constant values:
- 0x0 Boot. Needs to be loaded by the boot loader.
- 0x1: System. Needs to be loaded at kernel initialization.
- 0x2: Auto load. Needs to be started automatically.
- 0x3: Load on demand. Can be started manually.
- 0x4: Disabled. Should not be started.
TagREG_DWORDTag order constant.
Tag order constant value:
Indicates the order that services need to start within a given group.