Forward a message
Forward an email as quoted text to specified recipients. Source attachments are included only when explicitly supplied.
/api/v1/mailboxes/{mailboxId}/messages/{uid}/forward/Path parameters
mailboxIdintegerrequiredThe selected mailbox ID. Email access requires a current mailbox grant.
uidintegerrequiredThe message UID in the specified folder and UIDVALIDITY.
Maximum: 4294967295
Query parameters
folderstringThe mailbox folder name. Unicode names are supported.
Default: "INBOX" · Maximum 255 characters
uidValiditystringrequiredThe exact UIDVALIDITY returned by the folder listing. Stale values are rejected.
Request headers
Idempotency-KeystringrequiredA unique key for this intentional action. Reuse it only with the same request input.
Maximum 128 characters
Request body
Send JSON with Content-Type: application/json.
confirmMailboxstringOptional confirmation of the exact mailbox address.
Maximum 254 characters
tostring[]requiredRecipient email addresses. To, Cc, and Bcc combined must not exceed 20.
textstringPlain-text message body.
Default: "" · Maximum 1,000,000 characters
attachmentsobject[]Files to include. Up to 10 attachments and 5 MiB decoded in total.
Show child fields
filenamestringrequiredThe attachment filename.
Maximum 180 characters
contentTypestringrequiredThe MIME media type, such as application/pdf.
Maximum 120 characters
contentstringrequiredThe file bytes encoded as base64.
Maximum 7,000,000 characters
Responses
200Success
Durable operation receipt with this endpoint’s result. Pending provisioning and SMTP acceptance are distinct from resource readiness and recipient delivery.
400Invalid request
Invalid input or missing idempotency key.
401Unauthenticated
Missing, expired, or revoked bearer credential.
403Forbidden
Wrong credential purpose, insufficient scope, or missing mailbox grant.
404Not found
Resource or message not found or unavailable to this integration.
409Conflict
Resource conflict, stale message reference, ambiguous submission, or idempotency conflict.
413Too large
Request or message exceeds the supported size.
429Rate limited
Rate limited. Honor Retry-After before retrying.
500Internal server error
Unexpected server error. Contact support with the request ID; inspect uncertain writes before retrying.
503Service unavailable
Integrations disabled or an upstream service unavailable.
See limits and errors for retry handling and the error envelope.