Microsoft Security Essentials uses Microsoft Update to check for, and download definition updates every 24 hours. If you have a number of computers in your home or office without (or having limited) internet access, you may have to install the definition updates offline. To download the Microsoft Security Essentials virus and spyware definition update file, click the appropriate link below:
- Mpam-fe.exe for 32-bit (x86-based) version of Windows.
- Mpam-fex64.exe for 64-bit version of Windows.
Detailed information about this is available in Microsoft article How to manually download the latest definition updates for MSE.
Alternate Method
If one of your PCs having internet access has already updated itself with the latest definitions for the day, you can obtain the definitions from that system and use it in other systems that share the same architecture (x86 to x86, x64 to x64.)
Locating the Definition Updates Folder in the Source PC
1. Open the following folder path using Windows Explorer, by typing the following in Address Bar:
Windows XP
Windows 7 and Windows Vista
2. Double-click the {GUID} folder.
Note: {GUID} is a string whose valid format is {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} where X is a hex digit (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F). For example, the {GUID} string format might look like {A3EB313F-F9D9-442B-A191-2BA607752323}. The {GUID} string varies for each computer.
3. Copy the following files to a removable media.
| File name | Description (via Stuff n Things) |
| Mpasbase.vdm | Last base signature set of AntiSpyware definitions |
| Mpasdlta.vdm | Last delta signature set of AntiSpyware defintions |
| Mpavbase.vdm | Last base signature set of AntiVirus definitions |
| Mpavdlta.vdm | Last delta signature set of AntiVirus definitions again |
| Mpengine.dll | The AV Engine |
Transferring Definition Updates to another PC
Important: Before copying the definition updates to the target computer, disconnect from the internet, and then turn off Microsoft Antimalware Service via Services MMC. To disable Microsoft Antimalware Service, use these steps:
1. Press the WinKey + R keys to bring up the Run command.
2. Type Services.msc, and press {ENTER}
3. Right-click Microsoft Antimalware Service and click Stop
4. Minimize the Services MMC.
5. Open the following folder path using Windows Explorer:
Windows XP
Windows 7 and Windows Vista
6. Double-click the {GUID} folder.
7. Copy the definition updates from the removable media to this folder.
8. Maximize the Services MMC
9. Right-click Microsoft Antimalware Service and click Start
10. Open Microsoft Security Essentials user interface, and click the Update tab to verify if the definitions are successfully updated.
Related Posts
- How to Disable Updating of Definitions When Running a Command-Line Scan Using MpCmdRun.Exe
- Fix: Overlay Icon (With Blue Arrows) Missing for Network Folders Which Are Available Offline in Windows XP
- Updating Microsoft Security Essentials Using Command-Line
- Error “a .Bin File Is Missing” When Updating AVG Anti-Virus 8.0
- Microsoft Security Essentials Upgraded to Version 1.0.1961.0
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Despite all efforts, Microsoft Security Essentials is not getting updated. Every time error appears-’Failed 2 update’.
Please suggest solution.
With due regards,
Mehrotra
Wow, this tip is greeeeeeeeeat
I feel great being a Microsoft user, lets see how it works now…!
I have Windows 7 Ultimate x64 and when I click on Windows Update and then “View Update History”; I can see a lot of what are called “Definition Update for Microsoft Security Essentials”. I think that Microsoft automatically links the update through Windows Update as critical updates. Or maybe MSE somehow puts the definition updates in your update history for the user to view?
**@John Dangerbrooks**
That sounds like a great idea. Would you mind coming back here to let us know how it turns out.
Thank you. That was a great post.
Still, I’m surprised to see no MSE definition update on Windows Update user interface. Perhaps the reason is that Microsoft does not make the updates available through WSUS. (Mind you, doing so costs a lot of bandwidth for Microsoft)
But perhaps I can write a Windows PowerShell script or a C# application that automatically disconnect from Internet, disable Antimalware, copy updates, reactivate both and then distribute the updates over the network…?