Builds are available as a .ISO file download (see step #1 below)
Details
1) Use the link listed below download the appropriate .ISO file using the steps listed below.
https://www.microsoft.com/en-us/software-download/windowsinsiderpreviewiso
In the the Windows Insider Preview Downloads page, scroll down to the "Select edition" option.
2) Start by selecting an edition where you will see the most current Insider ISO builds and editions listed for multiple languages in both 32 and 64Bit versions.
Note: "Select edition":
A list the most recent builds currently available in .ISO format will be displayed as shown in the screen shot example listed below.
As of 04/07/21 Build 21354 is available for Dev Channel and 19043 for the Beta and Release Preview Channels.
3) Confirm your selection.
4) Select your language preference.
Current list of languages
5) Confirm your language selection. Note: FAST ring is now the DEV channel !
6) Choose either the 32 or 64Bit .ISO download for the Build number you selected (Build 21354 in this example)
Activation
Product key:
You will need to install the Windows 10 Insider Preview build on a device that has been previously activated with Windows 7/ 8.1 or with a Windows 10 product key. For more details please see the article: Activation in Windows 10. If you don't have a valid Windows 7 or Windows 8.1 or Windows 10 installed, an alternative is to download the Windows 10 Enterprise 90 day trial, (Use Disk Management to shrink your existing Windows 7 / 8.1 or 10 partition), and install Enterprise on the new partition or unallocated space, activate it, then join the Windows 10 Insider Program.
ISO file size (Properties) and Hash Code Value for build 21354:
Note: Both MS Edge and Google Chrome were used to validate that there was no difference
in either the file size or SHA1 Hash Code Value for the 64Bit English US version.
English (United States) File Size SHA1 Hash Code Value
Windows 10 Insider Preview (x64) Build 20354 | ISO File size (4,720,125,952 bytes) | 7093472a1559349ab649a13ac756e3f5de3d936d |
Windows 10 Insider Preview (x86) Build 20354 | ISO File size (3,540,721,664 bytes) | 1fe996ae3c074a3d8a330a7eba2af6b47fdb5ea3 |
English (United Kingdom)
Windows 10 Insider Preview (x64) Build 20354 | ISO File size (4,920,174,592 bytes) | 4640143675dab357835c5360fd9ecbff2771e472 |
Windows 10 Insider Preview (x86) Build 20354 | ISO File size (3,541,512,192 bytes) | 7536d406a51049e9403bc00cc2c6d058cf7e05b7 |
7) After downloading the correct .iso file, install the HashCalc utiliy and validate the SHA1 hash value listed above is correct.
HashCalc: http://www.slavasoft.com/hashcalc/index.htm
(Note: If the download is not corrupt, the value HashCalc returns will match the SHA1 value listed above.)
a) Launch HashCalc and navigate to the location of the .iso file you downloaded.
(The default download location is: C:\Users\User account name\Downloads)
b) Remove all check marks from the list of HashCalc options except for SHA1.
c) Click the ‘Calculate’ button and wait for the SHA1 string of letters and numbers to be displayed.
Note: The hash value is not case sensitive as upper and lower case letters are considered the same.
8) Next use ImgBurn (or Gear ISO) to create a bootable DVD.
ImgBurn: http://www.majorgeeks.com/files/details/imgburn.html
Note: When installing ImgBurn, choose the “Custom Installation (advanced)” option and remove the check mark(s) to eliminate unwanted options, including Optimizer Pro (I do not accept) which is not needed.
Burning ISO Images with ImgBurn article: http://neosmart.net/wiki/display/G/Burning+ISO+Images+with+ImgBurn
(The steps are the same for Windows 7, Windows 8 or 10), except you are not creating a Repair disc but a full installation DVD)
Note: Always use high quality DVD+R media and the slowest burn speed (4x or 6x) if offered a choice.
Note: Skip to step #4 to create a bootable Flash / Thumb drive.
9) For instructions on creating a bootable USB Flash drive to install Windows 7, 8 or 10:
Read: http://www.sevenforums.com/tutorials/2432-usb-windows-7-installation-key-drive-create.html
Windows 10 specific instructions: https://www.tenforums.com/tutorials/2376-create-bootable-usb-flash-drive-install-windows-10-a.html
Or: http://arstechnica.com/business/2009/12/the-usb-flash-drive/
Optional software to create a Bootable Windows 7 or Windows 10 DVD
Microsoft: http://support.microsoft.com/default.aspx/kb/977640
https://support.microsoft.com/en-us/help/15088/windows-10-create-installation-media
Rufus: https://rufus.akeo.ie/
Article Reference:
http://windows.microsoft.com/en-us/windows/preview-iso
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