Upgrading Drupal

I recently attempted to upgrade my site from 6.15 to 6.16, and somewhere in the process, the site got trashed. I had backups of everything, so I re-installed 6.15 and a dump of the database which didn't go as smoothly as hoped for, so something is still screwed up. On some admin pages, I get the following at the top of the page:

I have a rather strange problem. I upgraded the Drupal installation to 6.12 using synaptic package manager. Now I'm unable to access my site using the URL http://127.0.0.1/drupal6 nor did substituting "localhost" for the ip address worked. So I checked the processes (ps -A) to see if Apache is running and figured out that Apache wasn't running (When I had installed Ubuntu I had had it as part of the start up process).

I have some basic question about upgrade drupal version 6.13 to version 6.16?? we all know the content folder drupal version 6.16 is :
-includes
-misc
-modules
-profiles
-scripts
-sites
-themes
-.htaccess
-CHANGELOG.txt
-COPYRIGHT.txt
-cron.php
-index.php
-INSTALL.mysql.txt
-INSTALL.pgsql.txt
-install.php
-INSTALL.txt
-LICENSE.txt
-MAINTAINERS.txt
-robots.txt
-update.php
-UPGRADE.txt
-xmlrpc.php
and my question is :

Hi

I'm looking for some quick assistance please.

I'm trying to update my site (trellisscotland.org.uk) with some new modules. I logged in, set site configuration maintenance to offline, uploaded modules, ran update.php and started making custom changes. I hit a problem and (stupidly) logged off. I can't get back into the site now - I just get the off-line message.

I've restored my database, hoping to clear these settings, but still get the off-line message. I edited settings.php to allow free access to the site, but this has had no effect either.

Sorry if in wrong forum,

I have made a test environment using spikeWamp on a windows box and added drupal on top of this, the test site is a mirror of another remote site, all the modules that i FTP'D over from the remote site work except one when i enable this particular bespoke module i get a http 500 internal server error and then i get a user warning table already exists and duplicate entry errors,

any ideas anyone? thanks

My recently upgraded site has just been moved to a new server. Now running update.php results in the the "connection being shut down by server" (translation from Dutch) message in Opera.

After trying the same thing in Firefox opening update.php gives the desired first page (as does Opera) but when I click "continue" firefox actually offers to DOWNLOAD update.php

Updating was no problem on the previous (ageing)server.

Any thoughts?