How to Upgrade from v3.x to v4.0?

[joymax27104000]

Hello,

How to Upgrade from v3.x to v4.0?
I see this instruction:"For upgrades, upload the /install/ folder and see the 'Upgrade from v3.x to v4.0' option"
But need I upload any other folder (ex: theme, core, admin, plugins...)?

About pages: payment_complete.php, logout.php,...,faq.php >>> how about them? Delete or not?

Thanks for helping.

 

[pullvideos]

see the 'Upgrade from v3.x to v4.0' option" -> is a guide for manual upgrade
So you need to update any other folder and file to correct with v4 and update a patch database structure