Steps to fix it:

• If you're going to use your mobile data, make sure you've enabled mobile data in your Settings. You may be unable to access the internet if you are connected to a Wi-Fi network and notice an issue with the Wi-Fi sign in your status bar.
• Restart your computer.-Hold down the power button or the power and volume down buttons for a few seconds. Restart by pressing the Restart button. Wait for the device to turn off and on once more.
• The Download Manager should be reset.-Go to the Settings menu. Scroll down and select Apps. This option can be found in Settings > Application Manager on earlier operating systems. Select the Filter icon .Toggle the Show system apps option, then press OK. Scroll down to Download Manager, then tap it. Make sure the app is turned on (the icon should read Disable) To close this programme, press the Force Stop button. This will have no effect on the device's data. To confirm, press the Force stop button on the prompt.

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