Close question.
A 404 error normally means that what you request do not exist (not found). So perhaps the CardId is wrong somehow.
In general there do not seem to be anything generally wrong with the Trello API (I've made multiple attachments via the API today)
But the folder does exist when Make is requesting Trello to add it to the card?What do you mean with cardId is wrong?
According to the call you have a Trello CardId of '668abaa10b40da3a2ca56242' in th e request... If there is no card with this id, or the logged in user do B not have access to this Card you would get a 404
If I run the scenario agian, how can I check the CardId in Trello to see if they match?
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