Mount-WindowsImage -Optimize

According to Microsoft Docs, when you Mount-WindowsImage, you can add the Optimize parameter

The Optimize parameter reduces the amount of time it takes to initially mount the image. However, processes that are ordinarily performed during a mount will instead be completed the first time that you access a directory. As a result, there may be an increase in the time that is required to access a directory for the first time after mounting an image using the Optimize parameter.

The Test

I can test this in PowerShell using the following script to see how much longer it takes to Mount a Windows Image without using the Optimize parameter

The Results

I initially ran the script after a clean boot. After the first test, I swapped the processing order and rebooted to run the script a second time.

Win10 1809 x64

Win10 1809 x64 Optimize

54.881 seconds

64.306 seconds

48.171 seconds

78.166 seconds

As you can see the results were quite the opposite of what I expected according to the Microsoft Docs.


I cannot recommend using the Optimize parameter when mounting a Windows Image, add this to the fact that in Windows 10 1809 you cannot remove Appx Provisioned Packages offline when using Optimize


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