Windows Image Format (.WIM) Size Increases or Decreases with servicing

You may encounter the following scenarios when servicing a .WIM image

• Size of .WIM increases with each servicing change
• Size of .WIM does not decrease after removing files

When you modify an image, ImageX stores additional resource files that increase the overall size of the image. Exporting the image will remove unnecessary resource files.

In order to remove the unnecessary resources files from the .WIM, you will need to perform a imagex /export on a computer that has the Windows Automated Installation Kit (AIK) installed.

For example:

imagex.exe /export old.wim X new.wim "new wim"

Note:

• old.wim represents the original .WIM file
• X represents the image # you want to export
• new.wim represents the new exported .WIM file
• "new wim" represents the unique name for the image stored in new.wim.

 

To view the images present in a .WIM, you can use the following command:

imagex /info

 

More information on imagex.exe commands can be found at the following site:
http://technet.microsoft.com/en-us/library/cc749447(WS.10).aspx

 

 

Additionally you may see a slight performance improvement if you are booting from the .WIM(For example WINPE) by exporting it.  This process aligns the files and ensures there is no fragmentation. 

For more information on the WIM format see the following link:
http://www.microsoft.com/downloads/details.aspx?familyid=184706A3-6E05-4D9D-A034-830F4290EE42&displaylang=en

 

To download the Windows 7 WAIK see the following link:
http://www.microsoft.com/downloads/details.aspx?FamilyID=696dd665-9f76-4177-a811-39c26d3b3b34&displaylang=en

 

Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use for other considerations.