Problem
If you can not login or products are not stored in the shopping cart or get errors in the log like 'session_start failed', 'Failed to write session data', 'save_path is not writable', 'Invalid token session. Please login again'.
Solution
Session_save_path is a PHP variable that is set in php.ini, and on many shared hosting setups it’s actually set to a location that’s not writable.
Contact your host to solve this.
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