- First of all, check the SERVER_ROOT value in conf.php and make sure the value is set to a correct path.
More reading: http://phpgrid.com/documentation/installation/
- Check if the session is working on your web server .e.g. Apache, IIS, Tomcat. Make sure the session path is set to a valid path and given written permission. Run phpinfo() to find out and look for session.save_path
- Lastly, check the database column name including SELECT statement, primary key, foreign key, which could be case-sensitive on some systems.
- If you are using IIS as the webserver, check your app pool setting. If it defaults to a classic ASP app pool, Switched it to another one could do the trick as pointed out by one of our users.