I've got a few issues with a site but I'll try to separate in case they're not related.
Firstly I keep getting "Failed task - Deleting stale template caches".
I've looked in the logs and some messages include:
Encountered an error running task 3 (DeleteStaleTemplateCaches), step 156 of 166: An exception was thrown: CDbCommand failed to execute the SQL statement: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'dateCreated' in order clause is ambiguous
and
CDbCommand::fetchAll() failed: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'dateCreated' in order clause is ambiguous. The SQL statement executed was: SELECT
elements.id,entries.sectionId,entries.typeId,entries.authorId,entries.postDate,entries.expiryDate
dateCreated? – richardpixel Oct 27 '16 at 17:32