There are two definite Microsoft KB Articles that has fueled my research on how to Update Windows and MSE through a Proxy (Server/Address). In the Command Prompt window, enter: NETSH WINHTTP SET PROXY (Number and Proxy Server) Example: NETSH WINHTTP SET PROXY 22.214.171.124 or: NETSH WINHTTP SET PROXY MYPROXY.
See the links of KB Articles below: Here are the steps I have provided to allow WU/MU and MSE to update using either a Proxy Server or a Proxy Address in the MSE Forums and several other Microsoft Answers site forums: On Vista/Windows 7: 1.
If the issue is with your computer or a laptop/notebook you should try using the Reimage Plus Software which can scan the repositories and replace corrupt and missing files.
This works in most cases, where the issue is originated due to a system corruption.
However, when trying to update Microsoft Security Essentials either through the program itself or by checking for updates in Windows Update, some Windows users receive error 0x80072efd.
In addition to Microsoft Security Essentials, error 0x80072efd is also known to appear when trying to update Windows Defender.
If that is the case, simply navigating to Control Panel Uninstall a program and uninstalling/removing all of the third-party antivirus programs that you have on your computer.
Once you have uninstalled all third-party antivirus programs, restart your computer.
As soon as your computer boots up, you should be able to update Microsoft Security Essentials successfully.
Not having an antivirus program on your computer can leave it vulnerable, so as soon as you manage to successfully update Microsoft Security Essentials, download and install a third-party antivirus program other than the one(s) you were previous using.
Microsoft Security Essentials (For Windows 8 user see section 2 below): Microsoft Security Essential is a free Anti-Virus solution provided by Microsoft.
For installation of Microsoft Free Anti-Virus, it is essential that your PC must run a Genuine Windows.
It is recommended not to install any other antivirus on Windows 8/8.1/10.