I want customers to be able to create a fault report for our maintenance support board. I created an email address which creates a card on the right list on the right board, and it works fine when I or my maintenance manager test it. Having published the link to our customers with the intention that instead of mailing us they emailed their fault to the Trello board. So far only one person has done this successfully (it worked magnificently, and they even included a photo of the problem on the card!), the others are saying that the mail won't send.
Most of my customers are not techie, and the eMail address is very long and complex. I suspect that the process maybe too complex for someone who doesn't know, and doesn't care about what they are doing.
Can anyone suggest a simpler, foolproof, way of allowing the public to create cards on a list?