Windows 7

Microsoft's Windows 7 download site is only available to people with a retail product key (or "OEM System Builder" key).

You may be able to download a legitimate Windows 7 ISO file by using the tool at https://www.heidoc.net/joomla/technology-science/microsoft/67-microsoft-windows-and-office-iso-download-tool but that only provides a limited number of ISO downloads on a first come, first served basis starting on the first of the month at 0000 UTC.  For more information, see the following:

If you are willing to use an ISO file from August 2018 (5.5 GB), you can download that immediately.  However, if you want the original version, downloads are quite limited.  Notes below from the Heidoc support forum.

• "The download database on the server will be reset on the first day of every month. We will then generate one link per hour on a first come first served basis, whatever is requested, until all licenses are used up. The database is then again reset on the first day of the following month, and downloads can be provided again for some time." 
• "The Aug 2018 Win7 downloads are "standalone" edition downloads (only come with Home Premium, Pro & Ultimate as separate editions and not bundled together) that include IE11 & .NET 4.7.2 but are available in US English language only.  all post sp1 updates except the big KB3125574 rollup update are included."
• "I suggest you use the original version (NOT Aug 2018) since it is the official one and it can be unlocked to become a multi-SKU disc image. The only downside is you have to install all updates after the installation."  https://www.wincert.net/forum/topic/14731-is-it-just-me-or-is-the-official-client-fixed-resolutioned/
• https://www.wincert.net/forum/topic/14688-question-about-win7-iso/

For additional details, see:  https://www.wincert.net/forum/topic/14659-win-7-office-2010-monthly-download-days-starting-october-1-experimental/