This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
From the services window, right click on the service and choose 'Properties' from the menu. Then, click on the "Log On" tab. By default, it runs under the Local System Account. You will see a radio button that allows you to change the account. You'll have to enter the accountname and password. Then restart the service.