Upgrading Drupal

I upgraded to 5.2 and all is well except this message.
The directory files is not writable
Any help here?

Hi, in the 5.1 release I added this little code to run cron each hour because I cannot let the provider run the script as explained in some help page.

so I added this in index.php after drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);

I upgraded from version 4.7.6 to 4.7.7 and received a successful update notice (no failures, 100% on progress bar). However, when browsing to either site or site admin pages, I receive this error:

Fatal error: Call to undefined function block_list() in C:\Documents and Settings\John\Desktop\localhost\epnewX\includes\theme.inc on line 936

Can anyone assist me in resolving this issue?

Thank you.

I am receiving the following error when attempting to upgrade from verson 4.7.6 to version 4.7.7:

* user warning: Can't create table '.\epnew\cache_filter.frm' (errno: 121) query: CREATE TABLE cache_filter ( cid varchar(255) NOT NULL default '', data longblob, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid), INDEX expire (expire) ) /*!40100 DEFAULT CHARACTER SET UTF8 */ in C:\Documents and Settings\John\Desktop\localhost\drupalX\includes\database.mysql.inc on line 172.
* user warning: Can't create table '.\epnew\cache_menu.frm' (errno: 121) query: CREATE TABLE cache_menu ( cid varchar(255) NOT NULL default '', data longblob, expire int NOT NULL default '0', created int NOT NULL default '0', headers text, PRIMARY KEY (cid), INDEX expire (expire) ) /*!40100 DEFAULT CHARACTER SET UTF8 */ in C:\Documents and Settings\John\Desktop\localhost\drupalX\includes\database.mysql.inc on line 172.

I recently upgraded the version of drupal from 5.1 to 5.2 on my site http://www.vshiksha.com

Everything went absolutely smooth and upgrade was shown successful. But now, I am experiencing a problem. on any of my user account pages, I am getting an error as follows:

warning: Invalid argument supplied for foreach() in /path/to/public_html/modules/user/user.module on line 1516.

Please someone help me!

Regards
Satya Prakash Shukla

This is really a MySQL question, but since most everybody should already have a best method for this, I will ask it here.

What is the best way to merge the live site database with the test site database once the changes made to the test site are ready to be implemented and go live. To be clear, let me give an example.