Windows Service or Task Scheduler for maintenance tasks

Use the SC command, like this (you need to be on a command prompt to execute the commands in this post):

SC STOP shortservicename
SC DELETE shortservicename

Note: You need to run the command prompt as an administrator, not just logged in as the administrator, but also with administrative rights. If you get errors above about not having the necessary access rights to stop and/or delete the service, run the command prompt as an administrator. You can do this by searching for the command prompt on your start menu and then right-clicking and selecting "Run as administrator". Note to PowerShell users: sc is aliased to set-content. So sc delete service will actually create a file called delete with the content service. To do this in Powershell, use sc.exe delete service instead

If you need to find the short service name of a service, use the following command to generate a text file containing a list of services and their statuses:

SC QUERY state= all >"C:\Service List.txt"

For a more concise list, execute this command:

SC QUERY state= all | FIND "_NAME"

The short service name will be listed just above the display name, like this:

SERVICE_NAME: MyService
DISPLAY_NAME: My Special Service

And thus to delete that service:

SC STOP MyService
SC DELETE MyService

You have at least three options. I have presented them in order of usage preference.

Method 1 - You can use the SC tool (Sc.exe) included in the Resource Kit. (included with Windows 7/8)

Open a Command Prompt and enter

sc delete <service-name>

Tool help snippet follows:

DESCRIPTION:
        SC is a command line program used for communicating with the
        NT Service Controller and services.

delete----------Deletes a service (from the registry).

Method 2 - use delserv

Download and use delserv command line utility. This is a legacy tool developed for Windows 2000. In current Window XP boxes this was superseded by sc described in method 1.

Method 3 - manually delete registry entries (Note that this backfires in Windows 7/8)

Windows services are registered under the following registry key.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services

Search for the sub-key with the service name under referred key and delete it. (and you might need to restart to remove completely the service from the Services list)