I've already seen this issue once and had to completely delete the whole install and re-install fresh from softaculous in order to fix that. Hoping to avoid that this time around. Here is what happened and what I've done to try and fix it:
Client updated to 3.4.1, page then comes up that we just to need to update database, click here, this may take a few mins (paraphrasing). Did so, now whole site is blank white page, when going to sitename/wp-admin I get-
"You do not have sufficient permissions to access this page."
Tried all the following:
- deactivating all plugins to see if this resolves the problem.
- switching to the Twenty Eleven theme to rule out any theme-specific problems. (Did this through FTP by deleting current theme to try and force Twenty-Eleven, no change).
- resetting the plugins folder by FTP or PhpMyAdmin.
- re-uploading all files & folders - except the wp-content folder - from a fresh download of WordPress.
- running the upgrade manually via wp-admin/upgrade.php
When I try to run the upgrade from upgrade.php I get- "No Update Required
Your WordPress database is already up-to-date!
When I click continue I get redirected to the site with it's blank white page.