If you receive Windows Update error 80072f78, 80090305, or 8009033f while checking for updates, it might be caused by a connection interruption between your computer and the Windows Update servers. Close Windows Update, wait 10 to 15 minutes, and then run Windows Update again. You can also wait for Windows Update to run at its next scheduled time.
The Windows Update Troubleshooter fixes some problems with Windows Update, and it might resolve this error for you.
If that didn't work, try the following steps.
For more information about Internet connection problems, see Why can’t I connect to the Internet?
If you still receive this error after checking your Internet connection, it might mean that a program running on your computer is preventing Windows Update Services from accessing the Internet. Programs that might do this include firewalls, antispyware software, web accelerators, Internet security or antivirus programs, or proxy servers.
For steps you can take to fix this problem, see this article about connection-related update errors on the Microsoft website.
If you continue to see this error, go to the Microsoft Answers
website for more assistance.
Error codes this applies to: