The windows security center service can't be started.

This issue can occur if the Security Center service is not configured to run under the Local Service account but the dependent services are configured to run under the Local Service account.

To resolve this issue, make sure the Security Center Service and all its dependencies are configured to run under the Local Service account. Try these steps:
Step 1: Set the security center and its dependencies services to run under Local Service account.
a. Click Start, type services.msc and hit enter.
b. Double click on Security Center, click Log On tab.
c. Select "This account" click Browse button, type Local Service and click ok.
d. Type the password and confirm the password and click ok.

Note: Perform the same steps for Windows Management Instrumentation service.

Hi,  

Welcome to Microsoft Windows 7 Answers Forum! 

You may try the steps as below and check if the issue gets fixed.

Note we need to identify the “error code” that you are getting on your computer. The way to do this is to attempt manually starting the service from the Services Management Console.

To access the console type Services in the Start Search field, and press ENTER. You will need to click Continue if prompted to open the Services window.

In this window you need to locate the Security Center service right-click it, now select Automatic and select Start. When the service fails to start you will receive an on-screen error message.

Post the error information here so that we can better understand why the service is failing to start.

Note you need to disable any security software on your computer and check for the issue.

Now try to start your computer with default administrator account and check for the issue to do that follow the below provided steps.

1. Open the Local Users and Groups manager.

2. In the left pane, click on the Users folder.

3. In the middle pane, right click on Administrator and click on Properties.

4. To Enable the Buit-in Administrator Account -

     a) Uncheck the Account is disabled box. 

     b) Go to step 6.

5. To Disable the Buit-in Administrator Account -

   a) Check the Account is disabled box.

6. Click on OK.

7. Close the Local Users and Groups window.

8. Log off, and you will now see the built-in Administrator account log on icon added (enabled) or removed (disabled) from the log on screen.

NOTE: Click on the Administrator icon to log on to the built-in Administrator account.

Now from the above provided steps you need to check whether you are able to resolve the issue, if you are able to fix the issue with default administrator account then you need to follow the below provided step to create a new user account and check for the issue.

http://windows.microsoft.com/en-US/windows7/Fix-a-corrupted-user-profile

For further reference on this issue you may refer the forum link provided below.

http://social.answers.microsoft.com/Forums/en-US/vistasecurity/thread/49277301-85c2-4b13-9f71-1bd08e4688a0

Thanks and Regards:

Suresh Kumar - Microsoft Support.

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