Hi all,
something to share:
After my hosting provider upgraded the PHP version from PHP 5.2 to PHP 5.4, the expressionengine 2.4 started showing the the following error:
A Database Error Occurred
Unable to connect to your database server using the provided settings.
Filename: core/EE_Config.php
Line Number: 211(similar problem as on http://ellislab.com/forums/viewthread/228273/).
I then checked all the settings as mentioned in so many threads (SQL settings, database connections etc), but there couldn’t be a problem since there was NO changes made from the database side or even expressionengine. But I found out that there was a problem with upgrading PHP or changing environments in PHP, especially from an PHP 5.2 environment to anything higher (5.3 or 5.4).
The answer was found in
http://stackoverflow.com/questions/5915776/php-5-3-upgrade-cant-connect-to-mysql-server
There is a PHP 5.3 mysql driver restriction related to old authentication scheme hash stored in the database by previous mysql server. This could cause a problem with stored passwords so the databases will be unaccessible with old passwords.
To solve the problem you should recreate the mysql users with the same login and same password.
So, basically I recreated the same user name and password on the MySQL database used by expressionengine (on the MySQL control panel from the hosting provider), and voila, the blank screen disappeared and everything worked again.
Hope this might help a few of you out there with the same problem.
Good luck,
Amaravati