Considering Microsoft's free upgrade to Windows 10 from my current Windows 7. However, I may wait a while to see if any major issues arise for others by reading various forums.

I have discovered possibly one major issue: MS has made no provisions in the Win10 to upgrade or convert Windows Live Mail (Windows Live Essentials) which I have been using for many, many years. I do understand there are some many-step procedures trying to solve this; however, I do not want to loose all the existing folders and e-mails I have saved that are important to me. Now I'm getting nervous.

Why didn't MS include an automatic conversion for Windows Live Mail? It's their program?

WLM is alive and well in win 10, THERE IS NO NEED TO DO ANYTHING

Yes, upgrading from Windows 7 or a later version will preserve your personal files, applications and settings.

Backup your computer:

When making significant changes to your computer such as updating the operating system, you should always backup.