How To Fix 646 Windows Vista Update Error

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Error 646

The 646 error is a common problem for millions of Vista computers, which shows when you try and update your PC. The error will generally show because your system will be unable to correctly process the files or settings it requires to install the updates you require. The problem is mainly caused by some of the settings inside your PC being corrupted, but can also be caused by your system not having the correct permissions to install the updates you need.

What Causes The 646 Error?

The error you’re seeing is caused by your PC being unable to process the updates it requires. Every time you try and “update” your PC, it will continually look to connect to the Microsoft updates web server and then download the updates your system requires. The problem you have is either that your PC cannot correctly download the updates, or your system has some sort of issue preventing it from correctly connecting to the Internet & downloading the programs it needs.

Here are some typical causes of the 646 Windows Vista error:

• Your PC has some sort of Internet error
• Windows has settings errors preventing it from working correctly
• Your PC has some conflicting software

How To Fix The 646 Vista Update Error

Step 1 – Use “System Restore” To Roll Back Your PC

The easiest way to resolve this error is to use “System Restore” to fix the problems your PC may have inside. System restore is a common Windows feature which is used to help your computer to run like it did before it started getting errors without losing any of your data or other information. This feature is often overlooked, and can fix most of the errors which Windows encounters. You should begin your fix by using the steps below:

• Click “Start > All Programs“
• Go to “Accessories”
• Once in “Accessories”, click “System Tools”
• In “System Tools, you’ll find the button called “System Restore”, click it.
• Follow the on-screen instructions to restore your PC back to a date when you could update your PC

This will automatically re-send Windows back to the date that you decide, allowing it to repair any of the conflicts or errors which may be preventing the update from commencing. This should work for most people, but if it does not, you should look to use the next step:

Step 2 – Install The “Windows Update Agent”

The “Windows Update Agent” is a program issued by Microsoft to help process the updates that your computer requires to run. If you’re seeing the 646 error, it may mean that there are some updates that are either corrupt or incompatible with your system, leading your PC to run much less reliably when it tries to run them. This can be repaired by using the “Windows Update Agent”, which can be downloaded from this website near the bottom of the page.

Step 3 – Re-Register Windows Update DLL Files

A big problem that causes the 646 error is that Windows will actually somehow damage the files it requires for the updates process to run. If you have this problem, it’s recommended you resolve the issue by re-registering the files that could be damaged or missing. Here’s how:

• Click “Start > Run” (or press WINKEY + R)
• Type “CMD” into the box & Press Enter
• On the black screen that loads, type:
• regsvr32 wuapi.dll & press enter
• regsvr32 wucltux.dll & press enter
• regsvr32 wuwebv.dll & press enter
• regsvr32 jscript.dll & press enter
• regsvr32 msxml3.dll & press enter
• regsvr32 wups2.dll & press enter
• regsvr32 wups.dll & press enter
• regsvr32 wuaueng.dll & press enter

This will allow Windows to correctly read all the potentially damaged DLL files which may be preventing your PC from being able to read the files it needs to run the updates. If you try this and it doesn’t work, you should look to use the next step below:

Step 4 – Repair The Registry Of Your PC

• Download This Registry Cleaner

One of the biggest problems for Windows PCs is the way in which your computer will often damage a lot of the settings it needs to run inside the “registry”. The registry is a large database in the core of Windows which stores everything from your desktop wallpaper to your latest emails. Although this part of your PC is highly important, it’s continually causing a huge number of errors because of the way in which your PC  uses it so much.

One of the main reasons why the 646 error will appear is actually because the registry of your PC will somehow become damaged or corrupted, preventing your system from loading up its features correctly and leading your computer to run much less reliably as a result. To fix this problem, you should download a registry cleaner, install it and then let it fix any of the potential errors inside your system, allowing Windows to run much smoother again.