I am looking to add up all Values in Column E (quantities of products sold)
for each product by store.

The effect of this is that all Products that are the same (which are in
Column C) that relate to the same store (which are detailed in Column A) are
totalled up. I then wish to delete these rows (that have been added and are
thus no longer needed) - something likea subtotal except I only want the
'subtotal' rows

One way I thought I could do it might be add when A2=A3 AND OR C2 = C3,
these would continue progressing down my worksheet until A2 does not equal
A3 i.e. new Store and C2 does not equal C3 i.e. new product

Hope that make sense

Thanks