It sounds like you’re looking for a (Virtual Hard Disk) file — possibly for testing, development, or running inside a virtual machine like Hyper‑V, VirtualBox, or VMware.
Related search suggestions: (1) "Windows 8.1 ISO download Microsoft" — 0.9 (2) "Create VHD from ISO Hyper-V" — 0.8 (3) "Microsoft developer virtual machines download" — 0.7 windows 81 vhd download link
diskpart
create vdisk file="C:\win81.vhd" maximum=40000 type=fixed
attach vdisk
convert mbr
create partition primary
format quick fs=ntfs
assign letter=Z
exit
Then install Windows to that VHD using the ISO.image downloads previously provided by Microsoft for developer testing (such as IE11 evaluation) or for "Native VHD" boot configurations Windows 8
Here’s the legal, safe, and reliable method: Then install Windows to that VHD using the ISO
Open the Deployment and Imaging Tools Environment (part of the Windows ADK) and use the imagex or dism command to apply the install.wim file from the ISO to your VHD drive letter [1, 27].
If you are a web developer looking to test Internet Explorer 11 on Windows 8.1 specifically, Microsoft previously offered free VMs via the site (modern.ie).