diff --git a/changelog/71_UNRELEASED_xxxx-xx-xx.md b/changelog/71_UNRELEASED_xxxx-xx-xx.md
index 4dc459fe..d0c99308 100644
--- a/changelog/71_UNRELEASED_xxxx-xx-xx.md
+++ b/changelog/71_UNRELEASED_xxxx-xx-xx.md
@@ -8,7 +8,8 @@
 
 ### Stock
 
-- Performance fixes related to the stock overview and purchase/consume/inventory/transfer page
+- Fixed performance issues related to the stock overview and purchase/consume/inventory/transfer page
+- Fixed that the upgrade failed when having improperly defined product specific quantity unit conversions
 
 ### Shopping list
 
diff --git a/migrations/0207.sql b/migrations/0207.sql
index 081f9663..ff35c37e 100644
--- a/migrations/0207.sql
+++ b/migrations/0207.sql
@@ -40,8 +40,9 @@ INSERT INTO quantity_unit_conversions
 	(from_qu_id, to_qu_id, factor, product_id)
 SELECT p.qu_id_purchase, p.qu_id_stock, IFNULL(p.qu_factor_purchase_to_stock, 1.0), p.id
 FROM products p
-WHERE p.qu_id_stock != qu_id_purchase
-	AND NOT EXISTS(SELECT 1 FROM quantity_unit_conversions WHERE product_id = p.id AND from_qu_id = p.qu_id_stock AND to_qu_id = p.qu_id_purchase);
+WHERE p.qu_id_stock != p.qu_id_purchase
+	AND NOT EXISTS(SELECT 1 FROM quantity_unit_conversions WHERE product_id = p.id AND from_qu_id = p.qu_id_stock AND to_qu_id = p.qu_id_purchase)
+	AND NOT EXISTS(SELECT 1 FROM quantity_unit_conversions WHERE product_id = p.id AND from_qu_id = p.qu_id_purchase AND to_qu_id = p.qu_id_stock);
 
 -- ALTER TABLE DROP COLUMN is only available in SQLite >= 3.35.0 (we require 3.34.0 as of now), so can't be used
 PRAGMA legacy_alter_table = ON;