JET_errIndexMustStay

Code: 0xfffffa83 (4294965891)

As HRESULT:

S: 1 (Failure)
R: 1 (Part of the wrapped NTSTATUS severity, since N is set)
C: 1 (Customer-defined)
N: 1 (Wraps an NTSTATUS value)
X: 1 (Reserved, only expected on the TRK exceptions)
Facility: 0x7ff (Unknown facility)
Code: 0xfa83 (64131)

As NTSTATUS:

Sev: 3 (STATUS_SEVERITY_ERROR)
C: 1 (Customer-defined)
N: 1 (Reserved, must be clear in a well-formed NTSTATUS)
Facility: 0xfff (Unknown facility)
Code: 0xfa83 (64131)

Abstract

Cannot delete clustered index

Documented in Win32

Extensible Storage Engine Error Codes

The clustered index cannot be deleted.