MySQL Error : Unknown column 'newposts' in 'where clause'

The error indicates the query is referencing a column named newposts that does not exist in the session table. Given the reinstall over an existing site, the most likely causes are a schema mismatch (missing column), the code pointing at the wrong database, or an unexpected table prefix. @pritaeas' suggestion to inspect the database is correct; @Miklo_jan should not publish database credentials on the forum.

Recommended troubleshooting steps (safe, ordered):

• Make a full database backup before any change (phpMyAdmin export or mysqldump).
• Confirm which database and table prefix the vBulletin code is using (check includes/config.php).
• Inspect the session table structure with the database tools. Example checks:

-- replace yourprefix_ with the actual table prefix (or omit if none)
SHOW COLUMNS FROM `yourprefix_session` LIKE 'newposts';
DESCRIBE `yourprefix_session`;
SHOW CREATE TABLE `yourprefix_session`;

If the newposts column is missing, two non-destructive options exist:

• Re-run the official vBulletin upgrade routine (visit /install/upgrade.php for the installed code version). This will apply any schema changes required by the codebase.
• As a quick manual fix (only after a verified backup), add a simple integer column so queries can run:

ALTER TABLE `yourprefix_session`
  ADD COLUMN `newposts` INT UNSIGNED NOT NULL DEFAULT 0;

Notes and cautions: do not share DB credentials publicly. Prefer the official upgrade path because it preserves expected column types and other schema changes. After any schema modification, clear vBulletin caches or use AdminCP maintenance rebuilds so the board picks up the change. If the problem persists, paste the DESCRIBE output (with prefix redacted if needed) rather than credentials so the schema mismatch can be diagnosed further.