Can anyone from Holland (probably from Netherlands) help me?

Well you could always google the contact information of the bank and talk to them to see if its legitimate. Do not use the contact information in the email since it could be a fake from a scammer.

You come from spain, she from the netherlands, why would she use a bank in Switzerland?
Doesn't add up, one could just wire money from one iban mumber to another, though i can imagine both want some protection.

Just sell your pc in your own country on some second hand website and just save yourself the trouble.

I don't know anyone here that uses Zurich Cantonal Bank. I've never heard of it before.

I've read around on the bank's site a bit, and I couldn't find any section that tells sellers to ask for a shipment ticket.
Personally I live in Germany and this isn't common where I live either, at least from private person to private person.

For their contact number you'd have to replace the first 0 with +41 fyi, they take calls from 8 am - 6 pm CEST.
But as many said, there's no reason for a dutch person to be using a Swiss bank account, not for legit reasons.

I received 2 emails from Zurich saying that the money is being hold till I send them the shipment ticket

emails lol ... obviously a scam - cease all contact and ignore for good > a bank wouldn't contact you for
private <> private transactions, even if they did in writing / by letter that would be extremely suspicious

• why buy a PC from a stranger in Spain > not even on ebay it makes much sense
• also why would some plebeian daft cunt in the Netherlands use the Zurich Cantonal Bank
  ... couldn't be more fake

Let me guess: the address she gave you is some PO box?