Upgrading Drupal

I have a Drupal 6.6 from fresh installation and now when I simply tried to upgrade a module I was getting the error:

"An unrecoverable error has occurred. You can find the error message below. It is advised to copy it to the clipboard for reference.
Please continue to the error page"

The examples I found on using phpMyAdmin to Export a backup of the database had conflicting instructions on several of the check boxes under the section for Structure.

1. Add DROP TABLE
2. Add IF NOT EXISTS
3. Add AUTO_INCREMENT value
4. Enclose table and field names with backquotes
5. Add CREATE PROCEDURE / FUNCTION

The Lullabot video for upgrading to ver-5, check marks 3 and 4.

The http://drupal.org/node/120630 page check marks 1, 2, and 4.

Hello Guys,
I got a Problem with Drupal 6, when I upgrade my drupal 6.6 to 6.8.
I upgraded the website to 6.7 first and then 6.8.
Then I reload the website and I got this Massage:
Fatal error: Call to undefined function: system_region_list() in /www/htdocs/w0060b7c/includes/theme.inc on line 1758

Please help me or fix it.
Thanks.

Dracoo88

Just recently, someone installed a malicious code at index.php, as a result, the site went down. I attempted to find a duplicate copy of this file so I don't have to reinstall a new copy. This brings up several questions.

1) does an original file exist and where can I search for it. It must be for version 6.1 (or does it manner)?

2) if it doesn't, would reinstalling drupal 6.1 and dragging the other files (module, themes, images, etc) work without any problems?

Index.php was set to permission 644. I don't know how the code could have been manipulated.

After upgrading several Drupal sites from Drupal 5.x to Drupal 6.x, some of the menus have been lost almost on all of the sites.

I went looking in to MySQL database in the table menu_links and there I could see all the lost menu items written in the table, but the Drupal site wasn't showing them. I've tried to find out where there is a diference between workin and non-working menu items in menu_links table.

Here I'm posting two same menu items.
The first one is new, that I've manually created after upgrading --> it is working.
The second one in old, that has been upgraded from the older version of the site --> it isn't working.

FIRST ONE, NEW, MANUALLY CREATED --> IT IS WORKING

menu_name: menu-glavni-menu
mlid: 243
link_path:
link_title: Koristne povezave

options: a:1:{s:10:"attributes";a:1:{s:5:"title";s:0:"";}}
a:1:{s:10:"attributes";a:1:{s:5:"title";s:0:"";}}:

module: menu
hidden: 0
external: 1
has_children: 1
expanded: 0
weight: -48
depth: 1
customized: 1
p1: 243

SECOND ONE, OLD, UPGRADED --> IT ISN'T WORKING

menu_name: menu-glavni-menu
mlid: 77
link_path: #
link_title: Koristne povezave

options: a:0:{}

module: menu
hidden: 0
external: 0
has_children: 1
expanded: 0
weight: 0
depth: 1
customized: 1
p1: 77

I guess that the difference is in "options:" parrameter, but I have no ideal how it is created.

I just updated a site, which luckily is just a private wiki from 6.6 to 6.8. A lot of modules installed, but relevant ones might be Rules. Anyway, no errors or notices post install. Seemed to be going fine. But when I checked log files, which were checked just last night, no more Watchdog. Its gone. I no longer have ability to check / track page requests and such. Any recommendations on how to get this back?