🚫A profile won't start

When a profile's browser fails to open, LoginDeck does not use a toast that disappears. It shows a dialog titled The profile did not open, with the exact reason and a button, Open logs folder.

The message in that dialog is what identifies the problem. Find your sentence below.

🔍 Three things that are not failures#

Check these first, because none of them shows the error dialog.

• The Run button is animating. While a profile starts, its Run button shows the LoginDeck cards fanning open and closed, and it stays disabled for at least a second and a half. That is the browser starting, not a stall.
• A lock icon instead of Run. Your plan has locked that profile. See "Free is full", locked profiles and other plan messages.
• The whole window is frosted over with a card in the middle. This computer may not use this account. See "Computer limit reached".

🌐 "the saved proxy this profile uses has been deleted"#

A profile never falls back to a direct connection. If the proxy it points at is gone, the launch stops rather than sending your traffic out on your own address.

Open the profile's Proxy tab and point it at a proxy that still exists, or add the proxy back. See Give a profile a proxy.

Related messages, same fix:

• this profile's proxy cannot be read ({reason}) — fix it before launching — the stored address is not a shape LoginDeck can parse. Retype it. The accepted formats are in Add a proxy.
• the proxy device bound to this profile no longer exists — the phone it used has been removed from Proxy devices.
• phone "{name}" is offline — start the agent on it first — open the LoginDeck agent on that phone. A phone that is only mid-IP-change still launches fine.
• no proxy address for "{name}" — the server did not report a public proxy host — the phone is connected but the server has not published an address for it yet. Wait a moment and launch again. See Use an Android phone as a mobile proxy.

If the proxy exists and the launch still fails on the proxy, test the proxy on its own: A proxy won't connect.

⬇️ "the LoginDeck browser engine has not finished downloading — see the banner at the top, then launch again"#

The browsers are not inside the installer. On a fresh install the engine downloads once, and a banner across the top of the window reports it: Downloading Chromium engine — 42% (120 of 285 MB), then Verifying …, then Installing ….

Wait for the banner to go, then press Run again.

If the banner reads {name} download failed — {reason}, press Retry on the banner. A download that keeps failing is usually a firewall or a proxy on your own network blocking cloud.logindeck.com.

Version-specific messages:

💥 "the browser would not start"#

The full sentence is the browser would not start ({code}) — {reason}. Details: {path to the log}. The reason is one of three:

• the browser executable is not where the app expects it — reinstall LoginDeck — the engine files are missing or were quarantined. Reinstall over the top; your profiles are not in the program folder and are not touched.
• Windows refused to start the browser executable; antivirus or a damaged install are the usual causes — allow LoginDeck and its engine folder in your antivirus, then try again. If that isn't it, reinstall.
• the engine folder is missing its Chromium side-by-side manifest, so Windows will not start the browser — reinstall LoginDeck — an incomplete extract. Reinstalling is the fix.

🧱 "Chromium's sandbox could not read the engine, so the browser shut itself down"#

The full text ends LoginDeck tries to correct the folder permissions automatically — if this keeps happening, reinstalling is the fix.

LoginDeck repairs the engine folder's permissions itself on Windows, so this usually clears on the next launch. If it does not, reinstall. Installing somewhere unusual — a network drive, a synced cloud folder, or another user's profile folder — is the common cause.

⏱️ "the browser started and closed immediately (exit code {n})"#

The browser launched and then quit within a second and a half. When Chromium left a reason, the message carries it: Chromium said: ….

1. Press Run once more. A one-off is often a lock left by a browser that was killed.
2. If it repeats, open the log (Open logs folder → launch-<profile id>.log) and read the last few lines.
3. Antivirus is the most common cause on Windows. Add an exclusion for LoginDeck and try again.
4. Send the log to support if the same exit code keeps coming back.

🖥️ "That profile is open on another computer"#

Not an error — a question. This dialog names the computer and when it took the profile, and offers Open here anyway. Full explanation in When someone else has a profile open.

If your own browser closes by itself with the toast "{name} was taken over by {computer} — closed here", someone pressed Open here anyway on another machine.

⚙️ Messages when you start a profile from the API or a Flow#

• this profile is already running without an automation port — stop it first, then start it through the API — you opened it with Run earlier. Press Stop, then start it from the API or the Flow. The message says "through the API" even when you pressed Run in Flows.
• automation (API/MCP) is not supported for Firefox profiles yet — run it from the app, or use a Chromium profile.
• profile not found — the id you passed no longer exists.

⚠️ It opened, but a warning came with it#

A red toast reading "{name} opened on its stored clock ({timezone}) — the exit lookup through the proxy did not decide it: {reason}." means the browser is running but LoginDeck could not check where your proxy exits, so it used the timezone saved on the profile. If the proxy exits somewhere else, every checker will see the mismatch. Stop the profile, check the proxy, then launch again: A proxy won't connect.

📋 Starting many at once#

Run on a selection reports once at the end instead of one dialog per profile: "Started 12, 2 locked skipped, 1 failed — Profile 7: {message}". Only the first failure is named. Run the failing profile on its own to see its full dialog.

ℹ️ If none of this helps#

Email support@logindeck.com and attach:

• the exact text from the The profile did not open dialog
• launch-<profile id>.log from the logs folder (how to find it)
• your Windows version, and the LoginDeck version from the About page

See Contact support for the full list.