A closer look at Windows Update

In this post we discuss the importance of Windows Update and discuss:

• Purpose of Windows Update
• How does Windows Update work?
• Why sometimes updating Windows needs a reboot
• Getting rid of Windows Update’s nag to restart
• When is the recommended time to restart

Purpose of Windows Update

To avoid the hassle and possible lose of data caused by computer viruses and other malicious software which spread to PCs through portable devices and computer networks like the internet, Microsoft has developed a way to keep their operating system safe by providing security fixes and plugging vulnerabilities through an easy to use built-in application called Windows Update.

Another importance yet often overlooked benefit of Windows Update is to improve the performance of Windows as an operating system to performed its actions by optimizing the code thus making Windows more efficient. An example of such optimization can be an update to fix an issue with a hardware device.

Ok ok we get it…..Keeping your PC up to date is important but downloading, installing, and validating these updates for a  large number of PCs is no small feat as it needs a significant amount of time and attention.

Fortunately, there is an easier way, thanks to Windows Update, a free, built-in service included with Windows. This service helps you keep your PC more secure and reliable as well as compatible with devices and applications.  It provides a single location for getting updates and scheduling automatic updating.

Using Windows Update by itself, you get updates for Windows and new or updated hardware drivers which is why turning on Microsoft Update is recommended for all Windows PCs.

How does Windows Update work?

The Windows Update client operates in the background to download and install updates meaning that it doesn’t need the user to start or interact with it. In other words, it works in a silent mode not affecting your regular computer usage.

Checking for updates

The Windows Update client on your PC checks the Windows Update server at Microsoft for the availability of new updates at random intervals, every 17 to 22 hours. The randomization ensures that the Windows Update server is not overloaded with requests for updates all at the same time. The client only searches only for updates that have been added since the last time updates were searched, allowing it to find updates quickly and efficiently.

Downloading updates

Once the Windows Update client determines which updates apply to your computer, it will begin downloading the updates, if you have selected the option to automatically download updates. It does this in the background without interrupting your normal use of the computer.

To ensure that your other downloads aren’t affected or slowed down because updates are downloading, Windows Update uses the Background Intelligent Transfer Service (BITS) technology which downloads updates using idle bandwidth. This technology ensures that Windows Update downloads only when no other active download is in progress on the computer. This allows you to smoothly carry on day-to-day activities even while updates are being downloaded in the background.

Windows Update also supports pausing and restarting downloads. You do not have to worry if you need to shut down your computer, or if you have lost your Internet connection while an update is downloading. Once the connection is reestablished, the download will continue where it left off.

Installing Updates

When downloading is complete, depending on your Windows Update settings, the Windows Update client either installs the updates automatically, or else it notifies you of the download without performing the installation. You do not need to be logged in to your computer for Windows Update to automatically install updates.

Why sometimes updating Windows needs a reboot:

This is necessary because your PC may be insecure, or not fully updated, until a restart is completed. To decrease the number of computer restarts required, the client attempts to install as many updates as possible together. If you are using the computer, you may be given the option to postpone the restart (Later we will discuss how you can stop Windows Update from nagging to restart).

The main reasons for not fully updating until a restart are:

• The file needed to be updated is locked by process
• Re-initialization of application or service

The file needed to be updated is locked by process

As we discussed before Windows Update will attempt to download and install new, more secure, versions of the programs and services, so what if your PC is currently using that program at the time of installation? Well the operating system will signal that file as “locked” thus any changes needed to be done on that file will be postponed for the next start up.

Re-initialization of application or service

This case is a little different from the previous one. Usually to make the operating system more efficient it would cache the file in the memory, what that means is that a copy of the file would exist in the memory of your PC. When this happens the copy that exists on the hard disk is not in use so it isn’t locked by the application.

At the time of update, The new software is written to disk and any old code (such as dynamic link libraries or DLLs) already active in system memory usually remains untouched. This introduces a new problem since the memory contains an older copy of that file the system is not aware of the update.

To solve that issue, the PC has to shut down that application or service and start it from scratch so that a new copy is loaded on the memory.

When is the recommended time to restart?

Since these updates may contain security-related one that are aimed to protect your PC from virus, malware, and attacks, updates, the best recommendation is to restart as soon as possible to allow the updates to be fully integrated into your system.