Blocking an item to be ordered

[henriweigel]

How to block a customer to order an item, without prior ordering an other one? Example: We sell jewellery and boxes for jewellery; we do not accept a purchase order for one box only if one jewel is not ordered first.

[TraceyHand]

would you not be better to offer the "box" as an optional add-on component with the product?
That way it can only be ordered with the product and not on its own.

[henriweigel]

I'll try it.

Sorry for not replying faster... I was not on subject for days...

Best reagards,
Henri