The transaction does not work and Paypal shows this message:

We are sorry, we are experiencing temporary difficulties. Please try again later. 
If this error occurred while making a payment, avoid duplicate payments
by checking your Account Overview before resending a payment.

Message 3005

Paypal returns this message when your Paypal account's EMail has not been verified.

To verify your Paypal Email account, please follow the following steps:

• Log into your Paypal Account. You should be in the “Overview” tab.

• Click on your Email address, under “Business account overview”, you will be taken to a Web page listing your Paypal Email addresses.
• Select your Primary Adress.
• Click on the “Confirm” button.
• Follow the rest of the Paypal instructions.