some months ago you requested debug logs from that Topic:Vbps68wp2h51ifg6, but received no answer for almost half a year. But the problem still exists. In addition to the opener of the thread, there are currently two people facing this problem. I am not enough expert in SQL but I can provide you with all kinds of debug output needed. Like the thread opener we have also created a custom namespace, but the outdated index of the search engine was realized later. Therefore I can not clearly state a causal connection. Looking at the SQL statements in the debug output of updateSearchIndex.php the SELECT statement used for LOCK TABLES is completely the same as the one used afterwards causing the <code>Error: 1100 Table 'temp_rev_comment' was not locked with LOCK TABLES</code>. Any help would be very welcome.