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TWS API Debugging and Repair Guide

Review what to send before asking for Interactive Brokers TWS API debugging, integration repair, reconnect fixes, pacing issues, order rejects, or reporting cleanup.

13 MAY, 2026 .6 min read
Interactive Brokers TWS API Debugging
TWS API Debugging and Repair Guide featured image

Moore Tech Insight

TWS API debugging is not just endpoint troubleshooting. Interactive Brokers integrations can fail because of connectivity, account permissions, market data subscriptions, pacing limits, reconnect behavior, order state handling, or assumptions in the surrounding application.

Moore Tech offers TWS API programming for Interactive Brokers integrations, data tools, order workflows, reporting, repairs, and automation support.

What counts as TWS API repair

Repair usually means an API workflow already exists, but it is unreliable, incomplete, or failing under real operating conditions.

Common repair requests include:

  • reconnect or disconnect problems
  • order rejects or unexpected order states
  • missing or delayed market data
  • pacing violations
  • broken account, position, or execution reporting
  • old API code that needs cleanup before new features are added
  • tools that work manually but fail when left running

For these projects, logs are often as important as the code.

What to send for debugging

Send:

  • language and framework used by the current tool
  • TWS or IB Gateway version
  • API logs and application logs
  • screenshots of account or market data permissions when relevant
  • exact error messages or API callbacks
  • order workflow and expected states
  • market data symbols and subscription requirements
  • when the issue occurs: startup, reconnect, order placement, market close, or long-running use

If the problem is intermittent, include timestamps and what the application was doing when it failed.

Failure cases should be scoped

Interactive Brokers API work needs explicit behavior for disconnects, rejected orders, partial fills, unavailable data, pacing limits, and account changes.

Debugging should not only make the current error disappear. It should identify the operating assumptions the tool needs to handle.

Repair, wrapper cleanup, or rebuild

A rebuild may be better when the current integration has no clear state model, no logging, unsafe order assumptions, or too much code around the API wrapper to diagnose safely.

The existing tool may still be useful for understanding workflow, but the quote should reflect whether the right path is a focused repair or a cleaner integration.

Practical next step

Start with TWS API programmer services when you have API logs, broken order behavior, unreliable market data, reporting errors, or reconnect problems. Use the TWS API integration checklist if you need to organize the request first.