This has been discussed before.
The problem appears to be associated with running upgrade.php when it's not needed. Make sure upgrade.php, install.php, and update_to_FINAL.php are removed from your server.
If you do not have a backup, you have two choices - 1) do a clean install, or 2) manually edit the database.
For the database option:
Open phpMyAdmin and click on the database name in the left frame. Now in the right frame you should have a large box labeled Run SQL query/queries on database dbname
. Insert the script there and press Go.
Code: Select all
UPDATE phpbb_posts SET post_time = 1018224000 WHERE post_time = 0
This works if phpbb_ is your prefix, otherwise change it. I inserted today's date (as an Unix timestamp). I would recommend changing it to some other day, perhaps the board startdate. Use this calculator
to give you the timestamp. Just put the date in the right side and press the arrow button.
Let me if that works.