Deployment Image Servicing and Management is a command-line tool included in Windows Server 2012 and Windows 8 that is used to mount and service Windows Imaging Format (WIM) operating system image files. DISM is included in the Windows Assessment and Deployment Kit (ADK). In my testing, I found the versions match between what is installed automatically in Windows Server 2012 and Windows 8 and the version that ships with the ADK (version 6.2.9200.16384 as of this writing.
DISM GUI interface
Because DISM is a command-line utility, learning its syntax can take some time. For instance, you'd need the following syntax to install three custom device drivers into a mounted WIM image:
Dism /Image:C:\mount /Add-Driver /Driver:C:\drivers\1.inf /Driver:C:\drivers\2.inf /Driver:C:\drivers\3.inf
The navigation tabs in DISM GUI give you a pretty good idea as to the types of things you can manage with this free, Open Source utility:
- Mount Control: WIM image management
- Driver Management: Third-party drivers
- Package Management: Windows packages
- Feature Management: Windows features
- Edition Servicing: Product key and edition
- Unattended Servicing: Unattended answer files
- Application Servicing: Applications and application patches
Below I give you some examples of how you work with DISM GUI.
Mounting and unmounting WIM Images
From the Mount Control tab of DISM GUI, follow this procedure to mount a WIM image file.
- Click Choose WIM and browse to select your target WIM file. This can be a "stock" or a modified WIM file; it doesn't matter. If you get a "Permission Denied" error, try copying the WIM file from the optical source media to a folder on your system to which you (and Windows) has full control permissions.
Select the index number of your desired OS version. You can get a list of available images inside a WIM by clicking Display WIM Info.
- Click Choose Folder and specify the path where you want the WIM image unpacked.
- Click Mount WIM and let DISM GUI do its work. You can view the file system contents of the mounted WIM by clicking Open Mounted Folder. You can see my Windows 8 WIM mount in the screenshot.
- Unmounting a mounted WIM is as easy as clicking Dismount WIM.
Attaching an unattended answer file
As you probably know, you can use the Windows System Image Manager (SIM) from the Windows Assessment and Deployment Kit (ADK) to create an unattended answer script file to perform so-called "lite touch" Windows installations.
After you create the AutoUnattend.xml answer file by using Windows SIM, navigate to the Unattended Servicing tab in DISM GUI and follow these steps to associate the XML file with the currently mounted WIM:
- Click Choose XML to browse for and select your unattended answer file.
- Click Apply Unattend.xml to, well, apply the XML file to your mounted WIM.
You can view the DISM log at any time by clicking Tools > Open DISM Log, as shown in the screenshot below.
The DISM log provides very verbose information.
You can perform a WIM cleanup by clicking Tools > Cleanup WIM. A cleanup operation removes abandoned resources from a mounted WIM image.
In closing, I will remind you that DISM GUI does not do anything that you can't do directly through the DISM command-line interface or through the PowerShell layer. Essentially DISM GUI is a DISM host that provides administrators with familiar GUI controls, but that executes DISM statements "under the hood."