A T700 error is an error returned by Bacs. This relates to an issue with the Smart Card and the permissions configured on the card by your sponsoring bank. This can affect new and existing Smart Cards.
To check your Smart Card and to make sure the card is still set up correctly follow the article: How do I check my smart card is setup correctly?
This error can also occur when submitting via Faster Payments. You will need to check that your file has a fully numeric reference and there are no RTI references within the file.
Please Note: You cannot submit RTI files via the Faster Payments option.
If you are happy the card is setup correctly and that this is not a faster payments file with RTI reference, please ask your I.T department to check the 'comms.log' file. This is located in the ePay server installation directory on your ePay server. For help finding your server see article: How can I locate my ePay server?