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Power Automate errors / Schema

OpenApiOperationParameterValidationFailed. SendEmailV2 is missing required property 'Attachments/ContentBytes'.

platform: Power Automate / category: Schema / code: OpenApiOperationParameterValidationFailed

Cause

The Send an email (V2) Attachments array is missing the ContentBytes property, usually because the attachment object was built without all required fields.

Fix

Construct each attachment with both Name and ContentBytes: {"Name": "<file>", "ContentBytes": "<base64>"}. Use outputs('Get_file_content')['body/$content'] for the base64 content. Do not mix ContentBytes (V2) with the older Content property. Test by sending to yourself first.

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