Cannot access Plesk after upgrading to 10.0.1 (missing auth.php3)

[DennisF]

So I upgraded from 9.5.3 to 10.0.1 and now I cannot access the control panel (I just get a blank screen when trying to access it). After digging through the log files I found the following error message:

[Fri Nov 5 20:18:24 2010] [apc-warning] apc failed to locate auth.php3 - bailing
2010-11-05 20:18:24: (mod_fastcgi.c.2582) FastCGI-stderr: PHP Warning: Unknown: failed to open stream: No such file or directory in Unknown on line 0
PHP Fatal error: Unknown: Failed opening required 'auth.php3' (include_path='/opt/psa/admin/plib:/opt/psa/admin/javascripts:/opt/psa/admin/plib/locales:/opt/psa/admin/auto_prepend:/opt/psa/admin/htdocs/domains/databases/phpMyAdmin:/opt/psa/admin/htdocs/domains/databases/phpPgAdmin:/opt/psa/admin/smb:/opt/psa/admin/smb/application/library:/opt/psa/admin/plib/pear') in Unknown on line 0

And auth.php3 is nowhere to be found, searched the whole server and nothing.

Using Debian 5 x64.

EDIT: managed to solve the problem. Completely removed plesk/psa and all components, reinstalled them, ran autoinstaller, selected the components/options I wanted to use and I was good to go. Don't know why it failed the first time.

On a semi-related note, I kind of liked Plesk 9 more..