You cannot create a session when an error occurs, check the PHP or Web server log, and properly configure the PHP installation (win+linux) _php tips

Solutions under Windows:

Check to see if the directory exists or if the directory has write permissions for everyone or authenticated users by looking for a path to PHP.ini's Session.save_path = "". It's generally okay.

Solutions for Linux:

Today updated PHP, the result of the configuration of the phpMyAdmin landing in the "cannot create a session when an error occurs, check the PHP or Web server log, and configure the PHP installation correctly." "The mistake.

Error Reason:

PHP Update, overwriting the original/var/lib/php/session permissions, resulting in Apache users can not write session, resulting in this error.

Workaround:
Executive: #chown-R root:username/var/lib/php/session

Where username is the host user of Apache, I am Apache, so the command to execute is:
#chown-R root:apache/var/lib/php/session

If you also receive that error prompt, it is recommended that you do this:
#chmod-R 777/var/lib/php/session

Afraid of 777 of the permissions are too large, testing 770, 766, 776 can not solve the above problems, had to give 777 permissions first.
Do not know if there is a security risk in the use of the test, first write down this position.