macOS kernel return 0x1000000F (MACH_SEND_INVALID

Status / error code:		Category:

Constant name:
Source:		Operating System:
Description: A complex-message descriptor has an invalid type or disposition.

Previous	Next
MACH_SEND_TOO_LARGE	MACH_SEND_INVALID_HEADER

MACH_SEND_INVALID_TYPE

Descriptor metadata is part of the protocol

MACH_SEND_INVALID_TYPE means the kernel rejected descriptor metadata in a complex message. The descriptor type determines whether the body element represents a port, out-of-line memory, an array of ports, or another supported form; the disposition tells Mach what right or copy action to apply. A message can have a valid-looking byte buffer while still being invalid because these metadata fields do not describe a supported transfer.

Do not diagnose this solely as a peer-version mismatch. It can also result from using a descriptor structure with the wrong ABI layout, forgetting the complex-message bit, leaving padding or type fields uninitialized, or mixing generated definitions from different interface versions. The kernel may have processed some body elements before identifying the invalid one.

Practical checks

Construct complex messages from zero-initialized typed structures, not hand-written byte offsets.
Verify MACH_MSGH_BITS_COMPLEX, descriptor count, and every descriptor type and disposition.
Keep sender and receiver code generated from compatible MIG definitions where MIG is used.
Discard and rebuild a failed complex message before retrying.

References

Looking for a different code? Search another status or error code.