I've just upgraded MySQL as recommended by Plesk and we're now being hit with the following error when trying to access Sales -> Orders;
Item (Mage_Sales_Model_Order) with the same id "56321" already exist
Could this have been caused by the update? it wasn't a big update just an incremental one (we're on 5.5.54)
Any help is greatly appreciated
EDIT: I did actually place a test order on the site and deleted it shortly after using Magehit's extension Delete Order.
I assumed this wouldn't cause an issue as we've done it loads of times in the past.