It would help if you gave us a little more to go on. Is the error this one
Server Error in '/asp' Application.
The server rejected the sender address. The server response was: 501 Your domain does not seem to be valid. Could not find MX record for your domain. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Runtime.InteropServices.COMException: The server rejected the sender address. The server response was: 501 Your domain does not seem to be valid. Could not find MX record for your domain. Source Error:
This is because your email address is either invalid or blank. You can rectify this by going to the main UKTrainSim screen and then on the bottom left looking for "Change my info", click that and then you can update your email address. Once it's changed try ordering again and this time it should work fine.
If you have any further issues please drop us a note at
support@atomic-systems.com and provide as much detail as possible, including your username.