Troubleshooting & FAQ
The socket connects but Logon fails
Compare BeginString and both CompIDs from each side's perspective. Check credentials, clock, session schedule, TLS/network settings, and the sequence store. For FIXT.1.1, confirm DefaultApplVerID and both transport and application dictionaries.
Logon loops or reports sequence errors
The two stores disagree. Preserve logs from both sides, identify the expected and received sequence numbers, and decide whether recovery or a coordinated reset is correct. Repeatedly deleting one store hides the cause and can make the mismatch alternate sides.
Orders arrive but nothing is acknowledged
Check the live Overview overrides, then Sim Config behaviour, Reject Inbound, probability, matching rules, and instrument overrides. Confirm the message parsed under the active dictionary; malformed orders may take a reject path rather than the normal acknowledgement path.
Saved configuration has no effect
Wait for the save request to finish. Clear runtime overrides. Check whether the setting requires a session restart, and whether a narrower instrument, rule, or broker override wins for this order.
A routing rule never matches
Compare the incoming SecurityIDSource and SecurityID with the rule key exactly. Verify slice percentages total 100 and broker codes still exist. Send a non-matching control order to prove the default route independently.
A dictionary upload or assignment fails
Validate the XML and BeginString. FIX 4.x dictionaries must match the session version; FIXT.1.1 separates transport and FIX 5.0 SP2 application dictionaries. Check usage before replacing or deleting a named custom dictionary.
The page is stale but FIX traffic continues
REST data and SignalR live updates have different failure modes. Refresh the query or page and inspect browser/network diagnostics. Do not restart the FIX session until you know the engine, rather than only the live-update channel, is stale.
The demo is disabled
Pool exhaustion means the demo is healthy but no temporary lease is available. API failure produces retry or health errors. Wait for a lease in the first case; report the failing request and UTC time in the second.
What should a support report contain?
Operators and platform administrators can use Engine diagnostics to inspect session health, queued reports, pending timers, and recent logon failures. Check feed freshness before acting on the displayed state.
Include tenant, session ID, UTC time range, ClOrdID, expected result, actual result, relevant configuration, runtime overrides, and both message directions. Remove secrets and tokens.
Never paste FIX credentials, HMAC secrets, access tokens, or production customer payloads into an issue or shared chat.
Updated 2026-09-08 · Edit on GitHub