I'm sure this isn't new, but I can't find a good answer to why I can't install FSX. I'm running Windows 10. Ive tried different "fixes" but nothing seems to work.
You aren't suppling much information.
I'll guess that you have some of it on your computer.
Use this cleaner, then try installing again
https://www.revouninstaller.com/revo_uninstaller_free_download.html
Shut down your anti-virus (disable it).
Some anti-virus have a icon in your system try, right click on that and it will give you the choice of disabling it.
Do not disable your firewall!!!!!!
After it installs then enable your anti virus.
Let us know if this works.