Had this issue while configuring SagePay suite extension. When you went to place an order through Magento onepage checkout Sagepay throws an error: Payment has failed, please reload checkout page and try again. Your card has not been charged.
Seemed rather strange at first with everything seeming rather usual. After sometime of debugging, I decided to upload the sagepage suite files manually via FTP and whallaaah! issues solved!
Issue
Seems to be installing SagePay suite via Magento Connect.
Solution
Install SagePay files manually via FTP. Clean cache and give it another Go.
Hope you will find a little smile after this 
