Downloading Windows 7 from third-party "highly compressed" links is fraught with danger.
Instead of risking your PC with a highly compressed file, use these safer methods to get a legitimate copy of Windows 7. windows 7 iso highly compressed
When you see a "Highly Compressed Windows 7 ISO" that is only 500 MB or less, you are not looking at an official ISO. You are looking at one of three things: Result: A Windows7_Compressed
Right-click the entire C:\Win7Source folder (containing the stripped ISO contents) and select: windows 7 iso highly compressed
Result: A Windows7_Compressed.7z file approximately 1.1GB – 1.4GB.