Numerous DB errors

Hi, just installed wordfence on my Windows machine and I notice that my php error log is full of line like this one, any idea why and where I should look :

[10-Oct-2014 02:54:16 UTC] Erreur de la base de données WordPress Incorrect string value: '\xE9rimen...' for column 'filename' at row 1 pour la requête insert into wp_wfFileMods (filename, filenameMD5, knownFile, oldMD5, newMD5) values ('wp-content/uploads/2014/02/expérimentation-et-matière-14-222x160.jpg', unhex(md5('wp-content/uploads/2014/02/expérimentation-et-matière-14-222x160.jpg')), 0, '', unhex('50930B1B65A33547A6E937FF6E0424B5')) ON DUPLICATE KEY UPDATE newMD5=unhex('50930B1B65A33547A6E937FF6E0424B5'), knownFile=0 faite par do_action('wp_ajax_nopriv_wordfence_doScan'), call_user_func_array, wordfence::ajax_doScan_callback, wfScan::wfScanMain, wfScanEngine->go, wfScanEngine->doScan, call_user_func, wfScanEngine->scan_knownFiles_main, wordfenceHash->run, wordfenceHash->_dirHash, wordfenceHash->_dirHash, wordfenceHash->_dirHash, wordfenceHash->_dirHash, wordfenceHash->processFile, wfDB->queryWrite, dbrc_wpdb->query, dbrc_wpdb->dbcr_query

https://wordpress.org/plugins/wordfence/