Detailed Locimens desktop error symptoms, causes, and fixes for bridge, MT5, EA, LLM, risk, and updates.

Troubleshooting

Most problems show as a header banner, a toast, or a short sanitized message (Unauthorized, Login required, Request failed, Trading registration denied). Read the banner first — it usually links to the fix.

Quick symptom index

What you see	Go to
App won’t open, integrity / secure local interface dialog	App start & updates
Blank black window, Charts stopped responding	Charts & display
Reconnecting… / Sign in required	Account & session
Empty models, Connection Failed, Discovery Failed	AI & MCP bridge
No account/positions, AutoTrading banner	MT5 & data
EA Mailbox Not detected / License Pending or Blocked, handshake codes	Locimens EA
Registration banner, login owned by another account	Locimens EA
Live MT5 requires Pro…, Trading halted, Risk HALTED	Trading guards & risk
Plugin install failed, blank agent UI	Marketplace & agents

Fast checks

Stay signed in with the same email as locimens.com billing.
Keep MT5 running and logged in.
Confirm the MCP bridge is healthy (default localhost:3102); restart Locimens if not.
Open the header model list; confirm Settings → AI endpoint/key.
Follow every amber/red header banner before changing random settings.
After a crash: fully quit (including tray); last resort restart the PC.

App start & updates

Integrity: “could not verify its application files”
Reinstall from the official download. Restore files if antivirus quarantined them.

“Could not start its secure local interface”
Close duplicate Locimens processes, allow localhost in firewall/antivirus, then restart. Reinstall if it persists.

App update failed
Retry on a stable network; close MT5 and extra Locimens windows; use a fresh website installer if needed.

Blank / black window
Fully quit and reopen. On Windows Charts GPU blackouts, set LOCIMENS_DISABLE_GPU=1 and restart.

Account & session

Reconnecting to your account… — wait; if stuck, sign out/in.
Sign in required / Login required / Unauthorized — sign in again; after purchases, sign out/in once so entitlements refresh.
Empty Marketplace / Agent license expired — confirm account and plan; renew or update from Marketplace.

AI & MCP bridge

Empty models / disconnected — refresh header list; Settings → AI; start Ollama locally if used; enough RAM for the model.
Incomplete OpenRouter list — turn off Free models only in the header.
Connection Failed / Custom LLM test failed — re-test in Settings → AI; check VPN/firewall. Assistant-only failures: Settings → AI → Assistant.
Discovery Failed / missing tools — bridge Health; Marketplace → Manage plugins → Add MCP endpoints → Settings → MCP → Discover; restart Locimens.
Upstream / Proxy / Request failed — restart bridge/app; end hung processes. Sanitized Request failed hides file paths on purpose.

MT5 & data

Work through the Connection checklist as well.

No account/positions — MT5 logged in; bridge up; check AutoTrading / registration / EA banners.
Trade history error mentioning port 3102 — start MT5 + bridge, refresh Data.
Calendar / license errors — see Locimens EA; Refresh needs License Authorized.
MT5 AutoTrading is off (also retcode 10027) — Algo Trading toolbar (Ctrl+E); Tools → Options → Expert Advisors → Allow algorithmic trading.
Retcodes: 10016 invalid stops; 10004 requote (retry); 10030 filling mode; 10029 trail distance too small.

Locimens EA (Expert Advisor)

Calendar refresh, mailbox closes/trailing/breakeven, and many agent trades need the EA attached, mailbox discovered, and a cloud handshake (ea_session.json) while you stay signed in. Check Marketplace EA card or Settings → MT5: Mailbox (Running / Not detected) + License (Authorized / Pending / Blocked).

Read the pills

Mailbox Running — EA is publishing ea_hello.json. Not detected — attach EA or Settings → MT5 → Rediscover from MT5.
License Authorized — handshake ok. Pending — waiting. Blocked — failed; read the hint/banner CTA.
Locimens Downloads ≠ installed. Put .ex5 in MT5 MQL5/Experts, attach, enable Algo Trading (chart smiley).
Keep the desktop app open and signed in so the session can refresh.

Common EA errors

Symptom	What to try
Mailbox Not detected / “EA mailbox path not found”	Attach Locimens EA; Rediscover; override path only if needed (`…\MQL5\Files\AITrade_Mailbox`); restart MT5+app after switching terminals
Pending — EA detected, waiting for authorization	Stay signed in; register login/PC under Profile → MT5 & devices; wait 1–2 minutes
Pending / `no_handshake` — Install and run the Locimens EA…	No `ea_hello` yet; attach Full or Light build; wait ~60s
Blocked / “EA license handshake required…”	Follow banner CTA (Marketplace or MT5 & devices); agents will not mailbox-trade until Authorized
`ea_purchase_required`	Buy Full EA; Pro cannot use Light without Full purchase
`ea_release_expired` / Update EA / `update_required`	Download current release from Marketplace; replace Expert; reattach
`light_ea_live_blocked`	Light is demo-only — switch to demo or upgrade + Full for live
`light_ea_beginner_only` / `use_full_ea`	Wrong build — Full owners run Full; Beginner Light only on Beginner + demo
`login_required` / `handshake_failed`	Sign in; check network; note exact message for Support
Mailbox command auth unavailable	Update EA from Marketplace; reattach
Molly execution blocked / `ea_hello_stale`	Fix Authorized + registration; keep EA on chart; keep desktop open
Stuck mailbox path	Rediscover; clear bad override; confirm Common Files `locimens_mailbox_path.txt`
Registration denied / owned by another account	MT5 & devices with exact login; or switch login / contact support (no passwords)

Full vs Light: Beginner + demo → Light free download. Anyone else needing mailbox/calendar trading → purchase Full. Pro without Full purchase cannot handshake Light.

Trading guards & risk

Live MT5 requires Pro or higher — use a demo account or upgrade.
Logout grace / Trading halted (MCP bridge) — sign in; confirm subscription; restart Locimens; agents will not open new trades while the banner shows.
Risk Manager ON / Kill switch HALTED — Settings → Risk (Trading enabled, template, caps); Reset halt timer & counters; or Apply Follow Molly so Risk Manager stays OFF for Molly-only governance.

Marketplace & agents

Plugin install failed — confirm license/plan; signed in; healthy bridge; then Discover and Start if needed.
Blank or unstyled plugin UI — Start the plugin; restart Locimens; packaged UIs need relative asset paths.
Could not reach agent — Start from the agent panel; restart; reinstall/update from Marketplace.
EA file in Downloads but not trading — install into Experts, attach, verify Mailbox + License on the Marketplace EA card.

Charts & display

Charts stopped responding — Reload Charts or Go to Overview; full quit if the whole window went black; try LOCIMENS_DISABLE_GPU=1 after GPU zoom/pan issues.
Invalid script — fix JSON and re-import.

Still blocked

Collect account email, plan, OS, app version, MT5 demo/live, broker/server, whether the Locimens EA is attached, Mailbox/License pills, handshake code if shown, exact banner/toast text, and expected vs actual — then follow Getting support. Redact API keys and tokens.