Hi, this is driving me crazy.
I'm on CE 1.6 And Recently we have migrated our site to new server and everything looks great except Paypal express checkout.
What happens is after I click the PayPal checkout button in sidebar cart, I'm moved to the Login page of PayPal site. I enter an email & password and click Login. Immediately in the following page, I get an error message: "Your session has timed out, please log in again." It is now on the normal checkout page which shows products on the left and payment way options on the right. But the email input field on login section was empty and disabled which is not clickable at all. It is stuck and can't checkout.