Checkout - Joomla System message

Hello, im looking for a way to let my customer enter checkout part - CART without need to be logged in (or even registered). At the moment im getting joomla system message that user needs to be logged in.
What i need is the file (and the line), where its decided, that user which is not logged do not have permission to see his cart. I'd prefer that to some GUI interface configuration solution, because of possible further customization of generating those system messages.
Btw. I looked into Hikashop.js and found something, that i thought might be the cause, but even with the whole file commented, it still generates the messages.

Thank you for your reply and help!

Hi nicolas, you probably misunderstood..

There is nothing in HikaShop which restricts the checkout to registered users.

Im trying to remove restriction for guests, not for registered ones.

It's probably that you configured a menu item restricted to registered users in the Joomla menu manager and then configured the "force menu on checkout" setting of the HikaShop configuration to use that menu for the checkout.

I've got Force a menu on the checkout set to none, furthermore any of my menus is restricted.
And what im trying to get is access not to menu item, but to one exact part of checkout process - checkout cart, which is available only to logged users.
my page: dobreweby.sk/kp/

Thank you for any other help

What i am trying to achieve is checkout without registration, but with customer filling in his email and phone number, both would be bound with the order.
I was trying to make some changes to the code as the first step, hardcored registration type = 2 in login and registration view, which should mean guest checkout -> no registration (at least i understood it that way).
What happened is that although checkout asks the customer only for his email at the moment, it won't let him go through it, saying password needs to be set.
I tryied what u suggested - a bit of swapping in checkout and it seems it really was not about some kind of restriction to the cart part of checkout, but even if i make "login" last part of it, doesnt help much.
Btw. i do not have business version of Hikashop, so setting no registration in backend is not an option for me.

Thank you for any suggestions nicolas

I've made it, thank you very much for your assistence