For a while now I’ve been getting timeouts when using Windows updates through our proxy servers. Everything else seems to be working just fine, no complaints on browsing the web, it just seems that whenever I’m using Windows update through the proxy it takes a few times before it’s successful. Up until now it wasn’t really a problem because we use internal WSUS servers, however testing the Microsoft Operation Manager Suite and pointing Windows update to the Internet for getting the patches made it clear that connectivity issues were getting in the way of progress. Every time we scheduled an update run, it’s would time out on the proxy with error 0x80072ee2, direct connection went fine on all occasions. To make a long story short it turns out that the underlying mechanism of Windows Updates depends on the Background Intelligent Transfer Service (BITS), which in turn uses a different mechanism to connect to the internet (WINHTTP).
Normally it will use your Internet Explorer proxy to connect to the Internet, yet this seems to be having a few issues where Windows Update is unable to connect. What helped me in fixing the problem is telling WINHTTP to always use a dedicated proxy instead of relying of the automatic detection of a proxy or use the settings from Internet Explorer. Simply use good old netsh or use the powershell cmdlet:
Set-BitsTransfer
to accomplish this task.
List the current proxy
netsh winhttp show proxy
Set a proxy server
netsh winhttp set proxy <FQDN:Port>
Reset the proxy for winhttp
netsh winhttp reset proxy
Reference
Can’t download updates from Windows Update from behind a firewall or proxy server
How the Windows Update client determines which proxy server to use to connect to the Windows Update Web site
Windows Update Error List
https://support.microsoft.com/en-us/help/938205/windows-update-error-code-list
Netsh Commands for Windows Hypertext Transfer Protocol (WINHTTP)
https://technet.microsoft.com/en-us/library/cc731131(v=ws.10).aspx
Set-BitsTransfer
https://technet.microsoft.com/en-us/library/dd819421.aspx
Best Practices When Using BITS
https://msdn.microsoft.com/en-us/library/windows/desktop/aa362783(v=vs.85).aspx
