I get this message when on all pages of the admin or the site.
Warning: session_start() [function.session-start]: open(C:\Program Files\xampp\tmp/sess_df3067d3f1020b4b79f18666dc0375eb, O_RDWR) failed: No such file or directory (2) in /home/... .../wp-includes/plugin.php on line 395
The site isn't running on an XAMPP server so I don't know where the "C:\Program Files\xampp\tmp/..." is coming from.
Books still work but can't update any posts/pages when plugin is activated. I get this error as well:
Warning: Unknown(): open(C:\Program Files\xampp\tmp/sess_5467980ae04ebaf28ac392428006171f, O_RDWR) failed: No such file or directory (2) in Unknown on line 0
Warning: Unknown(): Failed to write session data (files). Please verify that the current setting of session.save_path is correct (C:\Program Files\xampp\tmp) in Unknown on line 0