Upgrading Drupal

After hours of frustration, and numerous attempts, (mostly involving changing file permissions and retrying), I have finally arrived at this error message. And am stumped with knowing how to proceed.

Fatal error: Class 'BaseTheme' not found in /var/www/html/drupal462/themes/xtemplate/xtemplate.theme on line 15

Any help?

I tried searching but came up with nothing.

When an anonymous site visitor (or a registered visitor who isn't logged in) comes to my site, they get the intro on the homepage that you get when you first install Drupal:

This is the solution to a minor problem I faced, I just hope someone may find it useful!

After migrating my Drupal site from MySQL 3.23.56 to MySQL 4.1.9 I got this error many times whenever I change something in the settings:

Access denied for user 'user'@'localhost' to database 'database' query: LOCK TABLES sequences WRITE in /var/www/html/drupal/includes/database.mysql.inc on line 66.

The Drupal version is 4.6.3.

Hi,

This isn't a problem as such but it concerns me. Since the upgrade I am getting a lot of messages like that above: user/123 denied access appearing in my logs (green highlighting).

Now I'm concerned there's something I've made a mistake with in upgrading from 4.4.2 to 4.6.3. Can anyone shed any light on this? At first I thought my users couldn't log in, but one definitely has and one of the messages is for my profile user/1 from about 3am when I was tucked up in bed.

So is it the robots checking old things or something?

Cheers
Theo

http://www.mysite.com/chatbox/?autolaunch=1

That is what comes up on the URL....and then it says PAGE NOT FOUND

HELP

I just upgraded from one of the 4.5.x versions to 4.6.3, and shortly after that, my Recent Hits, Referrers, Top Users, Top Pages, and the Track Node tab for each post just stopped updating. Cron jobs are running fine, so that's not it. What could have happened? Nothing has changed except for the upgrade, and even then, everything was fine for a couple of days after that.