Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm running Windows 7 Ultimate, 32-bit.

For the last couple of days, MSE doesn't fails to update, remaining stuck at version 1.75.119

I presume that an error log is created somewhere, or an event log, but I don't know where to find those.

It just says "connection failed". Tried it at home, at work and friends places, but never works. Restarted computer a lot of times now, checked for Microsoft Updates in general, but nothing shows up.

EDIT: I've opened a bounty for this, because I really don't know what to do anymore.

The oldest answer(the long post) here did not work.

Besides this problem, I'm having trouble using MSI installers too. I've had to add the SYSTEM group to a lot of maps and give them full control, but shouldn't the SYSTEM already be there?

Also, I had to remove the "read-only" attribute from the ProgramData and Users folders, add the SYSTEM group there too and give them full control. Only then will the MSI install work and even then, it says I doesn't have the rights to create a shortcut on the desktop. Don't know what I need to modify and where for that.

I'm saying this because I don't know how MSE updates, but if they use MSI files to do that, that might explain things.

The SYSTEM group remains added, but every time I take away the read only attribute, click OK and check the settings again, read-only is still active...

That's all I know.

Screenshot, all those updates were manual:

enter image description here

share|improve this question
up vote 4 down vote accepted

I know it might sound silly, but have you checked your computer for viruses?

share|improve this answer
Yes. MSE itself, Avast and AVG have all run complete scans, not the quick ones, complete scans. Not a single thing found, rootkits included. – KdgDev Feb 12 '10 at 9:12
@WebDevHobo: wait, are you running all three on the same system? That may be your problem right there... – AnonJr Feb 13 '10 at 16:15
No, I did them each separately, after the problem started to occur. – KdgDev Feb 14 '10 at 20:08
@WebDevHobo: you may want to use a boot disk to scan the drive as some viruses are noted for disabling AV programs once installed. Avira has a disk you can download at – AnonJr Feb 15 '10 at 14:03

I came across this problem approximately two weeks ago, I do not know what caused it, however the solution that worked for me was to manually download the latest updates and use them.

Here is the guide for doing it, and a direct link to X86 edition and X64 edition.

Hope this helps - if it doesn't, please say and I will try and dig up some information / help you further.

share|improve this answer
I downloaded and executed this, as detailed in the article, ran it as administrator. The file un-archived it all to an external hard-drive of mine, created a folder f:/2bab2e6b002b20e52ba63a84 and left it there. I then did the update from MSE, which failed. I ran the file as admin myself, tried the update again, which failed too. Is there a standard set of locations that MSE will check for this file? If so, I can move it and try again, yet I do not know this location. – KdgDev Feb 14 '10 at 20:21
Also, MSE always suggests I check to see if I'm connected to the internet and try again :P – KdgDev Feb 14 '10 at 20:22
That program should actually install the updates - take a look on the update tab - but do not click the update button and simply see what the date/version of the current definitions are. If it didn't install - take a look in the extracted folder for any .exe files and run them. – William Hilsum Feb 14 '10 at 21:11
I'm still at my old version. I finally uninstalled MSE. Think I'm gonna keep using AVG for the moment, see how that goes. – KdgDev Feb 16 '10 at 13:02

If it was all working okay a few days ago, the first thing I would try is a System Restore. This may also resolve the problems you are having with MSI installers too.

If the System Restore does not fix the MSE problem, but does fix the MSI problems, you could then try an uninstall and reinstall MSE from scratch.

In terms of the weird permissions issues, according to a Microsoft forum you can use the command below to reset the permissions on system folders and files:

secedit /configure /cfg %windir%\inf\defltbase.inf /db defltbase.sdb /verbose

More info can be found on Microsoft's knowledge base (the manual instructions also relate to Windows 7).

share|improve this answer
I suppose I could do a system restore, though I'm not certain on the full scale of the effects of such a thing. – KdgDev Feb 12 '10 at 9:30
If it all goes Pete Tong, you can always undo the system restore. It gives you the option to undo in the same place where you would pick the date that you want to rollback to. – Kez Feb 12 '10 at 10:24

If you're running multiple anti virus programs (MSE, Avast!, AVG?), you shouldn't be too surprised if one or more of these programs fail to work properly.

The only way to use multiple anti-virus programs is to disable the real-time protection,self defense and only use these programs for the purpose of scanning for malicious software.

So if you have three anti-virus programs that means actually they all run in background. When one anti-virus scans the virus vault of the others, it may look like it have files full of viruses and it will try to remove the file and will start malfunctioning and may damage your computer and saved data may also be erased. It may also cause random lockups to your computer.

You should remove all 3 programs properly (e.g. with the excellent AppRemover, it will find and uninstall any security applications on your system completely) and then install the one application you trust most.

share|improve this answer
I'm NOT running these at the same time. I installed them seperately, after this started to happen. I had one program do a scan, it gave no results, I uninstalled it. Same for the other. – KdgDev Feb 14 '10 at 20:07
@WebDevHobo - right, i still suggest to use AppRemover to uninstall MSE and reinstall the application, don't use the default uninstallers to remove anti virus software. – Molly7244 Feb 14 '10 at 20:25
I let AppRemover remove MSE, but the moment it started, I got several warnings saying the a couple of needed MSI files could not be found. They were all located in the Program Files map, but for some reason, MSE looked for them on Network drives with Drive letters that I've never connected before. – KdgDev Feb 16 '10 at 9:48

I have a simple solution: create your C:\Windows\Temp folder. Somehow, on some installations, the Temp folder is missing. I don't know why. But if you just go into C:\Windows and create a new folder named Temp and then try the update again, it will work. I wrote about this in a bit more detail in my blog.

share|improve this answer

Here are some steps from Mydigitallife that might solve your issue:

While waiting for Microsoft to fix and patch the occasional unable to auto update virus and spyware definitions error, here’s a few steps that user encounters the issue can take to ensure that Microsoft Security Essentials automatically update as and when needed.

- Ensure that Automatic Updates service (wuauserv) and Background Intelligent Transfer Service (BITS) is Running

Microsoft Security Essentials, although depends on client program to perform both client and definition update, but it still depends on the pipe of Automatic Update service (wuauserv) and directly, Background Intelligent Transfer Service (BITS) to carry out the udpate. So, ensure that wuauserv and BITS is running (via Control Panel -> Administrator Tools -> Services) or else MSE won’t update.

- Manually Update Microsoft Security Essentials

Microsoft Security Essentials can be forced to or manually update. To do so, just open up Microsoft Security Essential user interface, go to Update tab, and click on the Update button to check for updates.

enter image description here

Manually update will allow user to know if there is underlying problem with updating mechanism of MSE, or just the automatic update fails to perform the task.

- Force MSE to Check for New Definitions Update Before Running Scheduled Scan

This is a workaround for system where Microsoft Security Essentials does not or fails to check and update its virus and spyware definitions automatically. The trick is to schedule automatic scan on the system, and force Microsoft Security Essentials to check for new signature update prior to commencement of scan process. To do so, open up Microsoft Security Essentials user interface, go to Settings tab, select Scheduled Scan option.

Ensure that scheduled scan is enabled (Run a scheduled scan on my computer (recommended) check box is ticked) with daily interval, and check the checkbox for Check for the latest virus and spyware definitions before running a scheduled scan option. Unselect and uncheck the check box for Start the scheduled scan only when my computer is on but not in use so that scheduled scan will always run, and so do automatic virus signature update.

enter image description here

- Manually Download and Install Latest Microsoft Security Essentials Definition Updates

Microsoft is making available latest version of full engine and definition package from the Microsoft Malware Protection Center. User can download the package for free, and apply it to a PC running MSE, especially on computer without Internet connection.

- Increase Microsoft Security Essentials Virus and Spyware Definitions Signature Update Interval

The default 24 hours signature update interval of MSE may prove to be too long for some computers, as most computers are not leave to be running 24 hours everyday, causing Microsoft Security Essentials not updating virus and spyware definitions database to be out-of-date and put the computer at risk.

With a simple registry hack, Microsoft Security Essentials can be instructed to check for updates more than once a day (default is every 24 hours – once a day). Follow the guide below to change the registry key to allow MSE to check and update virus and spyware definitions signature database every few hours. Ability to perform and update process more frequently also able to solve the issue when MSE does not update its definitions database automatically.

Follow the guide to tweak the registry to change the Microsoft Security Essentials signature update interval:

  • Run Registry Editor (RegEdit).
  • Navigate to the following registry key:

    HKEY_LOCAL_MACHINE/Software/Microsoft/Microsoft Antimalware/Signature Updates
  • In the right pane, take ownership and grant full control permissions on a registry key, a REG_DWORD value named SignatureUpdateInterval.

  • Double click on the SignatureUpdateInterval. By default, its value is 24 (in Decimal) or 18 (in Hexadecimal). Change its value to any number between 1 and 24 (both inclusive) in Decimal.

    The numerical value determines how frequent and how fast (in hours) Microsoft Security Essentials will check for updates and update the virus and spyware definitions.

  • Restart the computer.

share|improve this answer
Automatic updates and Background Int... are on, but nothing from that end. The manual update is what I've been trying, which gives the connection errors. I've tried download the latest update, but not much from that either. I'll see if there's any change after a restart. – KdgDev Feb 8 '10 at 11:17

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.