This post: www.andrewbrettwatson.com/index.php/more/joomla-help/253-how-to-fix-the-joomla-3-0-error-displaying-the-error-page-application-instantiation-error-even-if-you-configuration-php-file-is-correct-and-unchanged

explains the issue. It was something with your db permissions.

unfortunately this link leads to a 404 error ;-(

Now my site on lifestyle.claire-fisher.net crashed out of the blue.
I have done nothing after succesful installation and was only surfing thorugh your other templates to look which i should apply to 3 different projects.
When I turned back to the frontend of lifestyle... I first got an error page and at reaload nothing anymore. In the backend I got this error message:
0 SQL=SELECT u.id AS value, u.name AS text FROM vtwiq_users AS u INNER JOIN vtwiq_content AS c ON c.created_by = u.id GROUP BY u.id, u.name ORDER BY u.name

It is strange as all my other joomla installations run well on the same server and also the 'native' installations of your template work well.
So what can be the case???

You can see it at Joomla!'s forums as well.
forum.joomla.org/viewtopic.php?t=791765

tks - i have read the postings and made some notes to check my database.
Right now I am trying to reinstall the demo site again and when I checked the configuration.php I see there databse settings:
public $dbtype = 'mysqli';
public $host = 'localhost';
public $user = 'templates';
public $password = xxxxx
I assume I have to exchange this against my own database settings - right?

Any more clues?

Hi again.
Unfortunately it was too early too joy, as my server crashed, what I suspect it came by a problem uploading the last nuevo.
However I am again struggling with the upload of nuevo quickstart page at blog.claire-fisher.net
I read and studied the facbok explanation for the Application Instantiation Error! and tried to check my confiiguration.php

But now the site shows up nothing anymore - just a blank page???
I am really down as I cannot find the cause.
Would you please helpm me and check what is wrong
.I can send you acees again if you send me a mail

Please helo as I am really desperate

in between my server crashed again:
ERROR: Zend_Db_Statement_Exception: SQLSTATE[HY000]: General error: 1 Can't create/write to file '/tmp/#sql_1c2_0.MYI' (Errcode: 122) (Pdo.php:234)

Could this be be the reason for the problems installing quickstart?
kb.sp.parallels.com/en/122303

It might be, but at this point you need to contact your hosting provider asap.