Hello/Hi/Greetings,

I've got two possible faults here.

One may be that the version of piwigo is out of date, but as I'm running on a NAS, using an APP Central version, I haven't got access to a newer version.

There may be an incompatibility between Piwigo ver. 2.10.2.r1 and PHP 7 ver. 3.12.0.r13 that needs addressing alongside the fatal error noted in the Subject line.

So, the fatal error - corrupt database?
Looks like this error indicates something to do with metadata or piwigo_config.sql.

Any ways of repairing it aside from restoring a backup? (I haven't got a recent backup).

Full text of the error:
Warning:  [mysql error 126] Incorrect key file for table './piwigo/piwigo_images.MYI'; try to repair it
SELECT c.id AS cat_id, id_uppercat, global_rank,
  MAX(date_available) AS date_last, COUNT(date_available) AS nb_images
FROM piwigo_categories as c
  LEFT JOIN piwigo_image_category AS ic ON ic.category_id = c.id
  LEFT JOIN piwigo_images AS i
    ON ic.image_id = i.id
      AND i.level<=0
  WHERE c.id NOT IN (44,95)
  GROUP BY c.id in /volume1/Web/piwigo/include/dblayer/functions_mysqli.inc.php on line 856


Fatal error: Uncaught Error: Call to a member function fetch_assoc() on bool in /volume1/Web/piwigo/include/dblayer/functions_mysqli.inc.php:220 Stack trace: #0 /volume1/Web/piwigo/include/functions_category.inc.php(507): pwg_db_fetch_assoc(false) #1 /volume1/Web/piwigo/include/functions_user.inc.php(436): get_computed_categories(Array, NULL) #2 /volume1/Web/piwigo/include/functions_user.inc.php(293): getuserdata(2, true) #3 /volume1/Web/piwigo/include/user.inc.php(60): build_user(2, true) #4 /volume1/Web/piwigo/include/common.inc.php(154): include('/volume1/Web/pi...') #5 /volume1/Web/piwigo/index.php(11): include_once('/volume1/Web/pi...') #6 {main} thrown in /volume1/Web/piwigo/include/dblayer/functions_mysqli.inc.php on line 220

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Piwigo ver. 2.10.2.r1
Running on Asustor NAS
MariaDB ver. 10.0.28.r28
PHP 7 ver. 3.12.0.r13