If there any way I can locate the file that launch its corresponding service? let's say I want to locate the file that launch the mrtRate service, how do I do that? any help would be appreciated

Services local to your machine are in your registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\*
it's a long list

start > run > (type in) services.msc

look for the service name and open its properties to see which executable it starts and the parameters it uses.

else, yes the registry is a good place to find out as well :-)

Thank you for the responds, I still have some questions wanted to ask:
1)if I install a certain software program, like firefox, nero, etc. will they install a service in the registry?
2)What is the purpose of service? what will happen if a certain service's stopped?
3)If I uninstall a program, will the service associated with that program get deleted as well(assume a program has one)?
I will be really grateful if someone can answer these questions for me, thanks.

(3) may or may not uninstall -- depends on how the installer was configured.

(1) A Service is a program WITHOUT a user window attached; runs in background;
may process requests from multiple users or programs. Eg:
Antivirus product, firewall, (at one time TCP was a service). VERY few programs install
a service along with the user GUI.

(2) If you stop a service (or disable it from running) then anything that depends upon it will fail and complain.

Here's a good rule; "If it isn't broken, then don't fix it!"

Hi, jobeard, thank you for answering my questions. So that means if I stop the WindDefend service, the Window Defender wouldn't be able to run, or if I stop the iPod Service, the iTune wouldn't able to run either(no music! ), am I right? Just couple more questions, and I'm DONE
1)How do I know whether a service is launched by window or the svchost.exe?
2)When I go into Window Task Manager, there're bunch of processes running under the Process tab, my question is how are those .exe being loaded in the window? what's the difference between a process and service? I know the svchost process is used to manage one or more DLLservice, but what about the others.
I really appreaciate your help! thank you!

Some additional information:

IF a program installs a Service and you disable the Service, the program won't run.

Most of the Services you see in the Control Panel> Administrative Tools> Services are part of the operating of the system. Some MUST be on Automatic so they start at boot. Some CAN be on Manual to start only when needed and Some CAN be disabled as not needed, not used or a security risk.

The following site will help you understand Services:
http://www.ss64.com/ntsyntax/services.html

The following will help to determine what services are running under a SVCHOST.EXE process:
http://www.bleepingcomputer.com/tuto...torial129.html

Thank you for the respond, the links you gave me is really helpful, I appreciate it

You're welcome. Let us know if you need more help.

A caution when working with Services: when changing the start up mode for a Service, it is always advisable to check the Dependency tab first. Some Services may depend on that Service running and that Service may depend on other Services running.