Cannot delete Warehouse

[leonidnk]

Hi,
After upgrade to 1.5.5.0 version I decided to use advanced stock management system. Thus, I established a new warehouse in Stock > Warehouses and configured all items and packs according to advanced stock management system. My shop did work OK.

Now I realized the advanced stock management system as too complicated and decided to use simple system as "I want to specify available quantities manually". Thus, I configuration all items and packs in Catalog > Products > Edit > Quantities and in Catalog > Products > Edit > Warehouses. Now no items are stored in warehouse. But anyway I got error message in all packs: "There is 1 warning. You must have a common warehouse between this pack and its product".

Another problem is I cannot delete the warehouse: "It is not possible to delete a warehouse when there are products in it". But no products in catalogue are connected to the warehouse. How I can delete the warehouse?

For clarity - The shop works as it has to work, but I do not like the error message and I want to delete the warehouse.
Please, help.