Installing Drupal

Earlier I was having problems updating from Drupal 7.15 to 7.16 so I decided to start fresh whereupon I installed the latest version of Drupal as well as my localhost software. No remnants of the earlier Drupal isntallments or data remained on my PC, I downloaded fresh copies of the latest version of both Drupal and Xampp. Everything was fine until I tried to install my new Drupal site (- or tried to call it with Localhost/drupal) it got the message that it was already installed and that AI needed to empty the database (which was, in fact, empty at the time.

Encountered the following error trying to upgrade from version 6 to version 7 running the update.php for my site . I have no idea what to do now !

DatabaseSchemaObjectExistsException: Cannot add index system_list to table system: index already exists. in DatabaseSchema_mysql->addIndex() (line 437 of /home/sawj/public_html/includes/database/mysql/schema.inc).

We have our drupal installation on a separate server from our web server. We are moving our drupal installation to a new server and have encountered problems. The database was copied over via mysqldump and all the files were copied over with proper permissions.

At first, it appeared to be working fine after the move except one module appeared to be acting up. I went and cleared the cache and then Drupal stripped all the theming code out of our site. It's now just a basic HTML site with no links to our theme's style sheets or anything from our page.tpl file.

Hi all, I have developed a site in Drupal 6. After server transfer, i saw that /admin* pages are showing "page not found". Others are all working such as /user* etc. Please help me the issue. What is the problem??? Please suggest me ASAP. Thanks in advance.

I have quiet a peculiar problem, as mentioned above -- taxonomy term fields are missing in content add form when users role doesn't have 'Taxonomy: administer vocabularies and terms' right turned on.
It happened some stage during installation. (You don't check every step with different user rights...)
What would be easiest way to handle such a situation? (Complication - there are already some content in site, worth ca 2 weeks work.)
I have no clear idea what really happened. Nothing in error messages.
Any ideas how to proceed?

When I'm installing Drupal 7.x, It gives me the following error: Can anyone help?