Can’t Login to Site Admin anymore – /wp-includes/capabilities.php on line 31

Hello. My WordPress won’t let me inside admin panel anymore. I was to upgrade it to WP 2.6, but when I upgraded the mysql, and then tried to log-in, i got following errors:

Warning: Invalid argument supplied for foreach() in /home/tomazgor/public_html/wp-includes/capabilities.php on line 31

Warning: Cannot modify header information – headers already sent by (output started at /home/tomazgor/public_html/wp-includes/capabilities.php:31) in /home/tomazgor/public_html/wp-includes/pluggable.php on line 479

Warning: Cannot modify header information – headers already sent by (output started at /home/tomazgor/public_html/wp-includes/capabilities.php:31) in /home/tomazgor/public_html/wp-includes/pluggable.php on line 480

Warning: Cannot modify header information – headers already sent by (output started at /home/tomazgor/public_html/wp-includes/capabilities.php:31) in /home/tomazgor/public_html/wp-includes/pluggable.php on line 390

Then i decided to upload the backup of the whole blog (mysql + wp 2.3 files) and the error stays the same ??

I looked inside this forum and tried with modifieing mysql base inside /wp-options/wp_user_roles … I deleted empty lines after last line in default theme/functions.php and some other stuff – nothing seems to work ??

Any help will be more then apreciated!!!

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