Response: Reject (“reject”)

Notifies peer that a received message is invalid.

Message Format

Field	Length	Format	Description
rejected message type	variable	variable length string	The command string of the message that is being rejected (e.g. “tx”).
rejection code	1 byte	rejection code	A code indicating why the message was rejected.
rejection reason*	variable	variable length string	A description of why the message was rejected.
rejection data	variable	rejection code specific	Optional extra data provided by rejection codes. For example, those that reject specific objects. Currently, all rejection codes that use this field fill it with the hash of the object being rejected, such as the transaction ID or block header hash, in which case the field is 32 bytes.

* rejection reason is a string providing a human language explanation of the reason the message was rejected.
This string is subject to change so client software SHOULD NOT use it programmatically.

Rejection Codes

Name	Value	Response To	Description
REJECT_MALFORMED	0x01	any	Message cannot be deserialized.
REJECT_INVALID	0x10	BLOCK, TX, FILTERSIZEXTHIN	Block or transaction is invalid, or xthin filter size is too small
REJECT_OBSOLETE	0x11	VERSION	This node no longer supports your client protocol version
REJECT_DUPLICATE	0x12	unused
REJECT_NONSTANDARD	0x40	TX	Transaction is non-standard, or not final as per BIP68.
REJECT_DUST	0x41	TX	Transaction has an output that is too small.
REJECT_INSUFFICIENTFEE	0x42	TX	Transaction does not pay enough in fees to be relayed.
REJECT_CHECKPOINT	0x43	unused