In this post I’m going to talk about some general steps which even an newbie can apply to fix many big update issues related to MSE/WD and even Windows Update.

Before beginning, you should rule out common causes. Very common causes are :

1. Faulty internet connection
   Please check if your browser (preferably IE) can browse internet or not.
2. Incorrect date/time
   Very common cause. You must have correct date/time for Windows Update to work.
3. Restart your PC and check if problem is still their or not.

Before beginning we should do some analysis of the problem. So the very first thing you have to do is to check whether MSE/WD is throwing any error code/error message after update has failed. If there is an error code then note it. If its not their then you may find MSE’s log file. It can be found here:
“%systemroot%\Temp\MpCmdRun.log”
(Don’t get confused by %systemroot%, it represents the folder where Windows is installed [normally C:\Windows] but if you have Windows installed in let’s say D: drive then it will represent D:\Windows, you should navigate to D:\Windows\Temp\MpCmdRun.log in that case)

After you open the log scroll down to very last line and see if any error code is listed their or not. Let’s say your log’s last lines were:

…………………………..
Update failed with hr: 0x8024001e
Update completed with hr: 0x8024001e
End: Signatures Update Service
MpCmdRun: End Time: ‎Mon ‎Sep ‎23 ‎2013 21:16:18
————————————————————————————-

You can clearly see that error code is 0x8024001e. Now if you have error code you can search it on internet and if you find any article from Microsoft Support then (hxxp://support.microsoft.com/kb/……..) you can follow it, do not go with other sites (specially forums like Microsoft Answers, Seven Forums, etc.) as their is no guarantee whether something written there is right or wrong and may contain variety of clumsy solutions that may even increase your problem. Note that even log may not have error code in some cases. You can proceed further in that case.

Next, check whether Windows Update is working or not. Its important step. MSE/WD update through Windows Update so if its not working then problem is not with MSE, but with Windows Update. If Windows Update is working well then problem is with MSE, which makes troubleshooting bit difficult. See this on how MSE updates:
MSE Definitions/Signatures Update FAQ

IF WINDOWS UPDATE IS NOT WORKING

First try Automated Troubleshooter, the Windows Update Fix it. It can be downloaded from here:
http://support.microsoft.com/kb/971058

Fix it normally solves the problem. But sometimes it may not work or may fix problem temporarily. Here are some things you can try if Fix it doesn’t work:

1. Restarting Microsoft Update service

<!– Copied from http://windows.microsoft.com/en-US/windows/error-0x8-encountered-while-virus-and-spyware-definition-updates-or-product-upgrades and added common solution and solution for Windows 8  –>

Common Step for all Windows

1. Open C:\Windows\System32\services.msc file.
2. Right-click Windows Update (Automatic Updates for Windows XP), and then click Start. If Start is unavailable, click Restart.

In Windows 8

If it doesn’t solve your problem then we have to do some ‘expert’ kind of thing. We will rename SoftwareDistribution folder. To do this you can download and run this BAT file (don’t worry I myself have created the file and it doesn’t contain any hidden virus, <wink>). You must run this file as Administrator (right click on BAT file and click on Run as Admin.) otherwise it will not work. It can be downloaded from here:
SoftwareDistributuion fix.bat

If this file doesn’t work the follow these manual steps:

1. Stop Windows Update service
   Stop Windows Update service by following the steps given in Method 1, but instead of clicking on Start or Restart click on Stop.
2. Rename SoftwareDistribution folder
   Navigate to C:\Windows –> right click on SoftwareDistribution folder –> click on Rename –> type “SoftwareDistribution.old” and hit enter.
3. Start Windows Update service
   Similar to Step 1, just you have to click on Start.

<!– Method 3, 4 & 5 are copied from http://support.microsoft.com/kb/2509997 and edited for better understanding –>

3. Resetting Catroot2 folder

1. Open Command Prompt as Admin. and type the following commands, and press Enter after each command:
   • net stop cryptsvc
   • md %systemroot%\system32\catroot2.old
   • xcopy %systemroot%\system32\catroot2 %systemroot%\system32\catroot2.old /s
2. Navigate to C:\Windows\System32 and delete all contents of the catroot2 folder, but do not delete the catroot2 folder.
3. Type the following command, and then press Enter in Command Prompt:
   net start cryptsvc
4. Exit the Command Prompt window.

4. Fixing Registry

1. Click Start, and then type “regedit” in the Start Search box.
2. In the Programs list, click regedit.exe.
3. Locate and then select the following registry subkey:
   HKEY_LOCAL_MACHINE\COMPONENTS
   (Note this registry key may not be present, if its not present then skip this method)
   
4. Right-click COMPONENTS.
5. Click Export.
6. In the File Name box, type COMPONENTS.
7. In the Save in box, click Desktop, click Save, and then save the file to your desktop.
8. In the details pane, right-click PendingXmlIdentifier, and then click Delete. If this value does not exist, go to the next step.
9. In the details pane, right click NextQueueEntryIndex, and then click Delete. If this value does not exist, go to the next step.
10. In the details pane, right click AdvancedInstallersNeedResolving, and then click Delete. If the value does not exist, go to the next step.
11. Restart the computer.
12. Try to install the updates again.

5. Registering Windows Update Files

1. Open an administrative Command Prompt window.
2. At the command prompt, type the following command:

   REGSVR32 WUPS2.DLL /S
   REGSVR32 WUPS.DLL /S
   REGSVR32 WUAUENG.DLL /S
   REGSVR32 WUAPI.DLL /S
   REGSVR32 WUCLTUX.DLL /S
   REGSVR32 WUWEBV.DLL /S
   REGSVR32 JSCRIPT.DLL /S
   REGSVR32 MSXML3.DLL /S

3. Try to install updates again.

IF WINDOWS UPDATE IS WORKING

If Windows Update is working then we got very less options. Problem lies within MSE and its bit difficult to find. Follow these methods serially and check after each step if update works or not:

1. Check for conflicting software

Many antiviruses leave their traces after uninstalling them which may result in conflict with MSE, causing it to malfunction. So you should remove them using their removal tools. You can download removal tools from here:
List of antivirus product removal tools

You can also try AppRemover which is scans and removes traces of almost every antivirus available.

2. Remove installed Virus Definitions of MSE/WD

Start Command Prompt as Admin. –> Type these codes (hit enter after each code):

cd “C:\Program Files\Microsoft Security Essentials” {“C:\Program Files\Windows Defender” for Windows Defender}
mpcmdrun.exe -removedefinitions -all
exit

It will remove installed definitions. Now try to update again.

3. Manually install Virus Definitions

By manually installing virus defintions, sometimes the problem within MSE/WD is fixed so its worth trying it. Download definitions from here:
http://www.microsoft.com/security/portal/definitions/adl.aspx

Note that this is not a solution, I said it may fix the problem. You should not take it as solution and regularly download that large file to update MSE/WD.

4. Reinstall MSE (for Windows XP, Vista, 7 only)

Uninstall MSE using any one method given here:Uninstalling MSE

Then download and install latest version of MSE from here:
Microsoft Security Essentials

If everything fails then post a question in Virus & Malware forum of Microsoft Answers with as much information as possible and the results of every method you tried (with a link to this post, of course!). If you came here through your own thread on Microsoft Answers then post the results of all steps you tried here in a reply in your thread.

Now comments are welcome! Please do rate, vote or comment. It helps me to analyze my article and please suggest any changes you want.