What does Windows error code 6730 (ERROR_TRANSACTION_NO_SUPERIOR) mean?

ERROR_TRANSACTION_NO_SUPERIOR

The requested branch operation assumes a superior coordinator that is not attached

ERROR_TRANSACTION_NO_SUPERIOR belongs to the Windows Kernel Transaction Manager transaction-processing model. A superior enlistment links a subordinate transaction branch to the coordinator above it. Operations used by communication resource managers to drive prepare, commit, or rollback toward a superior relationship require that enlistment to exist. A local root transaction can be perfectly valid while still having no superior because it is not a subordinate branch.

Determine whether the transaction was intended to be local, root, or imported from another transaction manager. If it should be subordinate, inspect propagation and branch-registration logs before the failing operation. If it is the root, the caller may be using a superior-only API on the wrong transaction. Record the transaction-tree role with each handle in the CRM layer. Creating an arbitrary superior after work has begun is not a safe generic repair because the transaction tree and recovery relationships must agree.

What to inspect

• Classify the transaction as root, local, or subordinate before invoking superior APIs.
• Check whether propagation successfully created the superior enlistment.
• Keep branch role metadata beside transaction handles in communication resource-manager code.

References

• Microsoft: superior transaction managers and superior enlistments
• MS-DTCO: superior and subordinate transaction-manager roles
• MS-DTCO: subordinate branch registration and two-phase commit
• Microsoft: KTM transaction, TM, RM, and enlistment functions