After updating your standard Antivirus package (eg: MCafee , Norton ) your Vista system might come up with an error on startup informing you that the Windows Defender Service could not be started.
Please follow the steps laid down below to resolve the issue in one go:
Step1 : Navigate to Network Connections and get into the properties of your preferred Network Connection and
take off the tick next to Client for Microsoft Networks.
Step2 : Open the Services Window and get into the Windows Defender Service , edit the startup type as Automatic and start the service.
Step3 : Reboot the system. At this point Windows Defender will come up with an yellow exclamation on the system tray. Don’t worry , just open the Security Center from Control Panel and Update Windows Defender, It will take some time to download and install the updates. Reboot your system.
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