NOT Resolve Fatal error: Class CI_Session_files_driver contains 1 abstract method

Head -> desk.

Hello,

That error also show on codeigniter forum open url
https://forum.codeigniter.com/printthread.php?tid=64763

Yes, because that's how you've named this thread.

Narf there no folder name contents in system directory

Contents is not a "folder name" ... use a dictionary to see what the word means.