NOTE: The above link describes about “Error code "0x80070646," "646," or "1606" when you try to install Office updates”
Please let me know whether the steps provided in the link above addresses your issue or not.
If the issue still persists, please reply to this email with the following information:
Are you getting any error message when you are trying to download the Windows Update or while trying to install Windows updates? If so, then please let me know as this would help us to find out the cause of the issue.
Please let me know if you are also getting any Error number along with the error message? Please mention the error number.
What is the type of Internet connection that you are using? Because we have different troubleshooting steps for dial up and DSL connections.
Have you tried any troubleshooting steps? If so, then please let me know so that we can avoid repeating the same steps.
Are you able to download any other files and software from Internet? If so, then please let me know so that we can find out whether it is the problem with Windows Update alone or the system itself.
What antivirus Software is installed in your computer? Sometimes the antivirus firewall may block the Updates.
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