How to Delay Loading of Specific Services

ID: Q193888

The information in this article applies to:

Microsoft Windows NT Server versions 3.51, 4.0

IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

SUMMARY

In some computers, especially older systems and those with slower peripherals, it may be necessary to delay the loading of a specific Windows NT service for the computer to boot properly. Or you may want to ensure that one service has started and is available for use before another for troubleshooting purposes. This can impact such issues as a domain controller, which cannot access the network where a protocol, or a service such as DHCP, attempts to load BEFORE the network card has had a chance to be bound (for example, Compaq Netflex).

MORE INFORMATION

You will first need to verify that the dependency you want to create does not already exist. The following are some of the most common dependencies that already exist in a default configuration:


   Service      Depends on
   -------      ----------
   Alerter      LanmanWorkstation
   Browser      LanmanWorkstation, LanmanServer, LmHosts
   ClipSrv      NetDDE
   DHCP         Afd, NetBT, TCP/IP
   Messenger    LanmanWorkstation, NetBIOS
   NetBT        TCP/IP
   NetDDE       NetDDEDSDM
   NetLogon     LanmanWorkstation, LmHosts
   Parallel     Parport
   Replicator   LanmanServer, LanmanWorkstation

The Registry subkeys for services are located in the following path and can control how services are loaded.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\<Service name>
WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).

To create a new dependency, select the subkey representing the service you want to delay and then click Edit and click Add Value. Create a new value name "DependOnService" (without the quotation marks) with a data type of REG_MULTI_SZ and then click OK. When the Data dialog box appears, type the name or names of the services that you prefer to start before this service with one entry for each line and then click OK.

The name of the service you would enter in the Data dialog box is the exact name of the service as it appears in the registry under the Services key.

When the computer starts, it will use this entry to verify that the service or services listed in this value are started before attempting to start the dependent service.

For example, you may want to ensure that your Server service loads before the Windows Internet Name Service (WINS). If you select the WINS key in the registry, you will notice that the DependOnService value already exists in the WINS key. In a default installation, WINS is already dependent on both RPCSS (Remote Procedure Call) and NTLMSSP (Windows NT LanMan Security Support Provider) services. To add the Server service to this list, double-click the DependOnService value. In the Multi-String Editor, on the line below NTMLSSP, add the entry "LANMANSERVER" (without quotation marks) and click OK.

NOTE: Entries in this field are NOT case-sensitive.

WARNING: Adding this entry manually may prevent the system from starting properly if you establish a "circular dependency." In its simplest form, such a problem would occur when you make two differing services dependent on one another. Neither service would be able to start as they would both require the other to be started first.

REFERENCES

For further information, refer to Chapter 8, General Troubleshooting, in the Windows NT Server Resource Kit.

Additional query words: registry dependency boot delay


Keywords          : ntstart 
Version           : winnt:3.51,4.0
Platform          : winnt 
Issue type        : kbinfo

Last Reviewed: March 31, 1999