I'm trying upgrading to 2.3 but I'm having two problems: my Dashboard and the Export functions seem to be broken. On the Dashboard, I get this error:
Warning: require(./wp-blog-header.php) [function.require]: failed to open stream: No such file or directory in /home/jurgenfa/public_html/dev/wp-content/plugins/index.php on line 4
The Export simply gives me an empty file.
I've double checked several times that I uploaded all files properly. Does anybody have any ideas how to fix this?