Microsoft Security Essentials includes a command-line utility which can be used to update the virus/malware definitions, initiate a scan, undo a recent definition update and perform other tasks. To know how to use the command-line utility, open a Command Prompt window (CMD.EXE) and execute the following command:
| Command | Description |
| -? / -h | Displays all available options for this tool. |
| -Trace [-Grouping #] [-Level #] | Starts diagnostic tracing |
| -RemoveDefinitions [-All] | Restores the installed signature definitions to a previous backup copy or to the original default set of signatures |
| -RestoreDefaults | Resets the registry values for Microsoft Antimalware Service settings to known good defaults |
| -SignatureUpdate [-UNC] | Checks for new definition updates |
| -Scan [-ScanType] | Scans for malicious software |
| -Restore -Name <name> [-All] | Restore the most recently or all quarantined item(s) based on name |
| -GetFiles | Collects support information |
In addition to the above information, detailed information for each command-line parameter is shown when you run the above command.
To update the MSE virus/malware definitions, use this command:
The command-line tool can be useful if you want to update MSE using Batch file, Script or using Task Scheduler.
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C:\Program Files\Microsoft Security Client\Antimalware>MpCmdRun.exe -scan -ScanT
ype 0
Because it’s supposed to be like this:
START msseces.exe -Scan -0
:)
I was able to update the virus definitions with the following code:
cd “%ProgramFiles%\Microsoft Security Essentials\”
MpCmdRun.exe -SignatureUpdate
But unable to start a scan with the following code in the same batch file:
START msseces.exe -Scan -ScanType 0
what gives?