Paypal & 2Co Payment Errors

Dears

I have been trying to configure payments for both paypal and 2checkout on my site through demo payments and i have the below errors:

Paypal

Once i have been directed to paypal sandbox (also tried in live mode) the below error appear:

				Error Detected
			

Your shopping cart is empty.

2Checkout

The payment process works perfectly while when finalizing the process to go back to my site through the approval URL that i have copied from cs cart to 2CO configuration

http://www.xswaar.com/index.php?dispatch=payment_notification.notify&payment=2checkout

The below error appears

503: Service temporarily unavailable

And this happens every time i have tried for 3 days.

You may try to buy something and try yourself (all payments are set on demo status)

www.xswaar.com

Thank you