Paypal has stopped working. I used paypal to process all of my credit card transactions on the backend, i am not referring to checkout via paypal as I do not have that option enabled.
The website is Magento based.
this is the error.
Order saving error: Notice: Undefined index: ACK in /srv/www/vhosts/mystore/docs/app/code/core/Mage/Paypal/Model/Api/[url removed, login to view] on line 600
We need someone to fix this problem.