If your Windows operating system may not be updating properly (see Control Panel\System and Security\Windows Update\View update history) via a proxy server, this instruction may help.

• right click Command Prompt (under Accessories) to run it as Administrator
• from the command line, to show if your proxy server is run in the background, issue

netsh winhttp show proxy

• if there's no proxy, run

netsh set proxy facultyproxy.upd.edu.ph:8080

• restart your machine
• to confirm the retention of the entry, run as Administrator from the command line

netsh winhttp show proxy

• update Microsoft Security Essentials.
• ensure that your Windows Update Settings include “Install updates automatically”
• run Microsoft Easy Fix
• run Windows Update Troubleshooter for Windows 8.1, Windows 8, and Windows 7
• restart machine and observe if Windows Update is working properly
• if not, run EACH line below manually from the command line as Administrator
  

net stop wuauserv
cd %systemroot%\SoftwareDistribution
ren Download Download.old
regsvr32 %windir%\system32\wups2.dll
net start wuauserv
NET START BITS
NET START WUAUSERV
SC QUERYEX BITS
SC QUERYEX WUAUSERV

• install the latest Windows Update agent
• restart machine and see if Windows Update is working properly

You may be prompted for your username and password to be able to use the proxy server to update Windows.

• How to fix Windows Update error
• How do I reset Windows Update components?