Troubleshooting¶

Start with the log at the bottom of the window. It says why something did not happen.

If something is simply not built yet, it is on the known limitations page.

ATC does not answer¶

After a transmission with no reply, the log has a No reply line with the reason, in words:

Reason	What it means	What to do
no controller on frequency	Nobody works the frequency you transmitted on	Check which radio is selected to transmit (TX), and its active frequency. The Frequencies card lists the right ones. On an airport's advisory frequency (advisory · no ATC) silence is normal: the log says "no reply expected"
sim paused	X-Plane is paused	Unpause. ATC is silent and deaf while paused
sim in replay	X-Plane is in a replay	Leave the replay
empty transcript	The speech recognition heard nothing	Check your microphone (below)
agent chose silence, readback accepted	ATC judged that no reply was needed	Normal after a correct readback or a remark. Look for the ✓ Readback accepted
busy	ATC was still handling your previous call	Wait a moment and say it again
error	Something failed	Say it again. If it repeats, send the log file

If ATC answers "Aircraft calling, say again", it did not catch your callsign. Say your full callsign clearly. If you fly under an airline callsign, say it as ATC says it ("Walker seventeen forty-five").

I cannot hear ATC¶

You hear ATC only on a radio that is tuned to the frequency, switched on, and selected to listen on your audio panel. If the log says a reply was "not played", the line says why: "isn't on COM1/COM2 active" (neither radio was tuned to it), or "COM1 is off", "COM1 isn't selected to listen", "the avionics are off".
A call you missed is said again. When the radio can hear it again within about a minute, and you have not transmitted since, ATC repeats its latest call on that frequency once.
ATC's audio waits while you are transmitting. Release push-to-talk.
Check Settings > Your setup > Audio > Speakers / headset. A headset you switched on after the client started appears after Refresh devices.

Cannot transmit¶

Pressing push-to-talk does nothing, and the log shows an Error line that begins "can't transmit":

The line says	What to do
the avionics are off	Switch the avionics on in X-Plane
COM1 is off (or COM2)	Switch that radio on. It is the radio selected to transmit, marked TX
COM1 isn't selected to listen	Select it to listen on your audio panel, or select the other radio to transmit
no aircraft state yet (is X-Plane connected?)	Start X-Plane: see X-Plane: not connected
answer the recording question in the xatc-agent window first	Choose Allow or Don't allow in the recording question
your recording choice is still being saved	Wait for the Saving settings box to finish, or choose Try again or Close if it says it could not save

Nothing is sent to ATC when a press is refused.

The log shows nothing after "You:"¶

Your microphone is not reaching the client.

Windows Settings > Privacy & security > Microphone: allow desktop apps. On Linux, check your desktop's sound settings and that the microphone is not muted.
Settings > Your setup > Audio > Microphone: pick the right device.
Push-to-talk releases when the window loses focus. To transmit while X-Plane has focus, use a yoke or joystick button.

X-Plane: not connected¶

The client and X-Plane must run on the same PC. X-Plane's Web API listens only on 127.0.0.1:8086.
Check Settings > Your setup > X-Plane: host 127.0.0.1, port 8086. (Under Advanced, Aircraft state from must be X-Plane 12 (Web API); that is how it ships.)
The client keeps looking every few seconds. You do not need to restart it after starting X-Plane.

X-Plane too old¶

The client needs X-Plane 12.1.4 or newer. It uses X-Plane's own Web API, and needs the version of it that arrived in 12.1.4.

The X-Plane pill reads X-Plane: too old, with "X-Plane 12.1.4 or newer is needed; this is 12.1.2" (the version your X-Plane reports), or "X-Plane 12.1.4 or newer is needed; this one is older" when your X-Plane is too old to say which version it is. When X-Plane is connected, the window's header shows its version after the client's.

What to do: update X-Plane 12 to the current release.

Tower will not clear me¶

Traffic. Tower waits for a departure ahead to be clear, and for an arrival on short final. It tells you why.
Wake turbulence. Behind a heavy, the wait is two or three minutes: "expect departure in two minutes".
No traffic data. If the client loses X-Plane's traffic feed, Tower holds every takeoff and landing clearance until it is back, because it cannot see the runway. A multiplayer or traffic plugin that takes over X-Plane's traffic can cause this.

Unable to access data, check connection¶

A red alert, and X-Plane is paused for you. ATC could not read its airport and procedure data, so it cannot control safely.

Check your internet connection.
When the data is back, the alert clears by itself and the log says "Data access restored". X-Plane stays paused until you unpause it.

Update required¶

The window shows a banner, Update required.: "This is xatc-agent 0.19.0, and 0.20.0 or newer is needed to fly." ATC needs a newer client than yours and has stopped connecting. Press Update now in the banner (it has no Later), or download the newest installer from the pilot site (app.7110atc.com, Download) and run it over your copy. If it says "No update was found yet", press Check again. Then start the client again.

Older than 0.20.0-rc.11: it cannot find updates

The pilot site moved to app.7110atc.com on 2026-10-20. A client older than 0.20.0-rc.11 still asks the old address for updates, so Update now and Check again find nothing. Install the newest version once by hand from app.7110atc.com/#/download; it updates itself from then on.

You see	What to do
Not signed in	Press Sign in. A sign-in lasts 30 days
Signed in · offline	The sign-in service cannot be reached. Your flight keeps going and the client keeps trying
"Your sign-in expires in ..."	Press Sign in again whenever it suits you. During a flight, sign in as the same account or the flight will end
"Your sign-in has run out. Sign in again to keep flying."	Press Sign in again
Your passkey is not offered, or is refused	Passkeys belong to the sign-in address, which changed on 2026-10-20: add the passkey again. Sign in with your email, password and the authenticator's code, then add the passkey again
"This flight belongs to another pilot"	You tried to rejoin a flight another account started. Press New flight
"Your account isn't allowed to fly"	Ask the owner
"Can't confirm this flight's pilot right now. Retrying."	Nothing to do. The client reconnects by itself and your flight is kept

The window¶

It opened in my browser instead. On Windows the window needs Edge WebView2, which ships with Windows 10 and 11; on Linux it needs WebKit2GTK. Without it the same page opens in your default browser and works the same.
On Linux I have to sign in every time. Staying signed in needs a keyring (GNOME Keyring or KWallet). Without one, the sign-in lasts only while the app runs.
"xatc-agent is already running". Only one client runs at a time. Starting it again brings the window that is already open to the front. If the line adds that the window could not be brought forward, look for it in the taskbar.
I closed the client mid-flight. Start it again within about ten minutes and choose Rejoin last flight.

The radios will not tune from the window¶

The 1, 2 and ⇄ buttons write to X-Plane. They are greyed out while X-Plane is not connected; hover over them for the reason. Only real VHF COM frequencies are accepted (118.000 to 136.990 MHz).

Reporting a problem¶

Check the known limitations first. Then send the owner:

What you said and what you expected, with the time.
The log file: Settings, at the bottom, Open log folder. It never contains your sign-in or any audio.