M
185
Call a Pro
MongoDB · Database Server & Atlas
MongoDB server reported: Prepared Transaction In Progress.
Quick Answer
Error code 185 on your MongoDB Database Server & Atlas means: MongoDB server reported: Prepared Transaction In Progress.. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. MongoDB returned code 185 (PreparedTransactionInProgress) while processing this request path.
  2. Atomic commit/abort guarantees could not be upheld for the in-flight operation.
  3. Transaction coordinator state changed, forcing retry or rollback logic.
How to Fix It
1
Review logs/telemetry for code 185 (PreparedTransactionInProgress) and capture the exact command and parameters that triggered it.
2
Load full transaction/session trace to identify the exact conflicting transition.
3
Retry the whole transaction flow (not partial fragments) with idempotent boundaries.
4
Review coordinator logs to distinguish retriable aborts from terminal state conflicts.
5
Add monitoring for recurring PreparedTransactionInProgress events so future incidents are detected and triaged faster.
Pro Tip
This issue typically requires professional diagnosis. Attempting this fix without proper training could cause further problems.
Related Error Codes
Video Guides
Loading video guides…
Search more on YouTube →