Once you have the official ISO (approx 3.0 GB), compress it using in .7z format with these settings:
Microsoft’s final official ISO for Windows 7 (released in 2018) included Convenience Rollup KB3125574. This ISO is for 64-bit. That is the baseline. Anything significantly smaller has been altered. highly compressed windows 7 iso file
An ISO file, also known as an ISO image, is a type of file that contains the contents of an optical disc, such as a CD, DVD, or Blu-ray disc. In the context of Windows 7, an ISO file typically contains the installation files for the operating system. Compressing an ISO file involves reducing its size while maintaining the integrity of its contents. This can be achieved through various compression algorithms and techniques, which aim to eliminate redundant data and represent the information in a more compact form. Once you have the official ISO (approx 3
800 MB – 1.2 GB. This ISO will boot, install, and run—but it will lack many features. Anything significantly smaller has been altered