Scheduled tasks have stopped processing usage logs

Thanks for the reply. I really appreciate your help. I have followed your steps above (i.e., moved the log out of processing into stage, updated the time stamp to 48 hours earlier, reloaded the backend in the browser, I can see the log file has been moved back into the processing folder). I then found the following php error message. Any idea how I can fix it?

PHP Fatal error: Call to a member function getGenreId() on null in F:\journals.lincoln.ac.nz\wwwroot\plugins\generic\usageStats\UsageStatsLoader.inc.php on line 78
PHP Warning: assert(): DefaultOverrideHeaderChildThemePlugin failed in F:\journals.lincoln.ac.nz\wwwroot\lib\pkp\classes\plugins\PluginRegistry.inc.php on line 228
PHP Warning: assert(): DefaultOverrideHeaderChildThemePlugin failed in F:\journals.lincoln.ac.nz\wwwroot\lib\pkp\classes\plugins\PluginRegistry.inc.php on line 228
PHP Warning: assert(): DefaultOverrideHeaderChildThemePlugin failed in F:\journals.lincoln.ac.nz\wwwroot\lib\pkp\classes\plugins\PluginRegistry.inc.php on line 228
PHP Warning: assert(): DefaultOverrideHeaderChildThemePlugin failed in F:\journals.lincoln.ac.nz\wwwroot\lib\pkp\classes\plugins\PluginRegistry.inc.php on line 228

This seems to be the same error message for another issue I’m trying to solve on Error message when downloading View report - #9 by asmecher

Since these two issues are all related to usage stats, it may be caused by the same data problem?

Yanan