IN7504 Posted October 27 Report Posted October 27 Good morning, I installed FSUIPC version 7.5.4 for MSFS and MSFS2024 to use Java Simulator peripherals. FSUIPC doesn't connect to the simulator, and if I launch the simulators via the FSUIPC application, they close. Until last week, everything was working fine. I attach the details of the error screen: FSUIPC.FSUIPCException: FSUIPC Error #9: FSUIPC_ERR_NOTOPEN. The connection to FSUIPC is not open. in FSUIPC.FSUIPCConnection.ReadLVar(Byte ClassInstance, String LVAR) in JS_Connect_V4.MIP_FENIX.timer_CHK_Tick(Object sender, EventArgs e) in System.Windows.Forms.Timer.OnTick(EventArgs e) in System.Windows.Forms.Timer.TimerNativeWindow.WndProc(Message& m) in System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) ************** Assembly caricati ************** mscorlib Versione assembly: 4.0.0.0 Versione Win32: 4.8.9310.0 built by: NET481REL1LAST_C Base di codice: file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/mscorlib.dll ---------------------------------------- JS-Connect_V4 Versione assembly: 1.0.0.0 Versione Win32: 1.0.0.0 Base di codice: file:///C:/FSUIPC7/JS-Connect/JS-Connect_V4.exe ---------------------------------------- System.Windows.Forms Versione assembly: 4.0.0.0 Versione Win32: 4.8.9256.0 built by: NET481REL1LAST_B Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll ---------------------------------------- System Versione assembly: 4.0.0.0 Versione Win32: 4.8.9320.0 built by: NET481REL1LAST_B Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll ---------------------------------------- System.Drawing Versione assembly: 4.0.0.0 Versione Win32: 4.8.9032.0 built by: NET481REL1 Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll ---------------------------------------- fsuipcClient Versione assembly: 3.3.12.414 Versione Win32: 3.3.12.414 Base di codice: file:///C:/FSUIPC7/JS-Connect/fsuipcClient.DLL ---------------------------------------- System.Configuration Versione assembly: 4.0.0.0 Versione Win32: 4.8.9032.0 built by: NET481REL1 Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll ---------------------------------------- System.Core Versione assembly: 4.0.0.0 Versione Win32: 4.8.9316.0 built by: NET481REL1LAST_C Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll ---------------------------------------- System.Xml Versione assembly: 4.0.0.0 Versione Win32: 4.8.9032.0 built by: NET481REL1 Base di codice: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll ---------------------------------------- Accessibility Versione assembly: 4.0.0.0 Do you have any advice for me? Thank you very much.
John Dowson Posted October 27 Report Posted October 27 (edited) 18 minutes ago, IN7504 said: if I launch the simulators via the FSUIPC application, they close. What do you mean by this? FSUIPC does not launch MSFS. The desktop icon installed with FSUIPC only starts MSFS, and then MSFS will start FSUIPC via the EXE.xml (if/when using the auto-start feature). 18 minutes ago, IN7504 said: FSUIPC doesn't connect to the simulator Does this occur with both MSFS2020 and MSFS2024? If FSUIPC is not connecting, I need to see your FSUIPC7.log file - please show me / attach this. If there are connection issues, see the following FAQ entry: 18 minutes ago, IN7504 said: Until last week, everything was working fine. What has changed since then? John P.S. Do you mean 7.5.4 (not 7.4.5)? If so, were you previously using 7.5.3? If so, I can provide you with that version to check its not an issue with the new version. Edited October 27 by John Dowson PS added
IN7504 Posted October 27 Author Report Posted October 27 Good evening, Mr. Dowson, thank you for your timely response. Yes, until two days ago I was using version 7.5.3. I'm having this problem with both MSFS2020 and MSFS2024. When I launch one of the two simulators using the icon generated by installing FSUIPC, a screen appears saying "FSUIPC is preparing the cabin. Please what..." and then closes shortly thereafter. Andrea FSUIPC7.ini
John Dowson Posted October 28 Report Posted October 28 12 hours ago, IN7504 said: When I launch one of the two simulators using the icon generated by installing FSUIPC, a screen appears saying "FSUIPC is preparing the cabin. Please what..." and then closes shortly thereafter. Yes - those icons start MSFS and display the 'preparing the cabin' splash screen while MSFS starts-up. Does MSFS actually then start? Once it starts, MSFS should then start FSUIPC - you will see the FSUIPC splash screen when this is starting (unless you have disabled this). If MSFS is not auto-starting FSUIPC7, then see this FAQ entry: You can also start FSUIPC7 manually (by double-clicking the FSUIPC7.exe) to see if the issue is just that FSUIPC7 is not running. If it is running but cannot connect, I need to see you FSUIPC7.log file (not the FSUIPC7.ini file which you attached). If there were issues installing the auto-start component (i.e. updating your EXE.xml files), then there should also be an error in your InstallFSUIPC7.log file, so take a look at that. You can also show me / attach this file. John
IN7504 Posted October 28 Author Report Posted October 28 6 hours ago, John Dowson said: Yes - those icons start MSFS and display the 'preparing the cabin' splash screen while MSFS starts-up. Does MSFS actually then start? Once it starts, MSFS should then start FSUIPC - you will see the FSUIPC splash screen when this is starting (unless you have disabled this). No, MSFS won't start, the screen closes, and nothing happens. If I start it using the traditional icon, the simulator loads correctly, but without FSUIPC.
John Dowson Posted October 28 Report Posted October 28 3 minutes ago, IN7504 said: No, MSFS won't start, the screen closes, and nothing happens. Ok - then we need to determine why MSFS isn't being started. Can you show me / attach your InstallFSUIPC7.log file please. Are you using a steam or a MS Store installation for MSFS2020/MSFS2024? 5 minutes ago, IN7504 said: If I start it using the traditional icon, the simulator loads correctly, but without FSUIPC. If MSFS is not auto-starting FSUIPC7, then you need to see that link I previously posted. Your installation log may also tell you what the issue is here. Your application cannot connect if FSUIPC is not running. Have you tried starting it manually?
IN7504 Posted October 28 Author Report Posted October 28 6 hours ago, John Dowson said: You can also start FSUIPC7 manually (by double-clicking the FSUIPC7.exe) to see if the issue is just that FSUIPC7 is not running. If it is running but cannot connect, I need to see you FSUIPC7.log file (not the FSUIPC7.ini file which you attached). If there were issues installing the auto-start component (i.e. updating your EXE.xml files), then there should also be an error in your InstallFSUIPC7.log file, so take a look at that. You can also show me / attach this file. John, I'm attaching the requested file. I launched FSUIPC via .exe and it starts correctly, but it doesn't connect with Java Simulator's JSconnect. FSUIPC7.log
John Dowson Posted October 28 Report Posted October 28 19 minutes ago, IN7504 said: I'm attaching the requested file. As I keep saying, I need to see your InstallFSUIPC7.log file - please attach that.... 19 minutes ago, IN7504 said: I launched FSUIPC via .exe and it starts correctly, but it doesn't connect with Java Simulator's JSconnect. Your log shows a few connection attempts before a connection to MSFS was established. This was because you manually started FSUIPC7 to early - when manually starting, you should wait until MSFS has arrived at the main menu. Other than that, the log looks ok. Did you start your java program before or after FSUIPC was connected to MSFS? Try starting it once FSUIPC7 is connected to see of that helps, or after you have an aircraft loaded and ready-to-fly. I have also attached the previous version for you to try, 7.5.3. Temporarily rename your current FSUIPC7.exe and use this to see if there is a difference. FSUIPC7.exe
IN7504 Posted October 28 Author Report Posted October 28 Ok I started FSUIPC after the simulator started and then I started JS Connect and the error appeared: FSUIPC Error #9: FSUIPC_ERR_NOTOPEN. The connection to FSUIPC is not open. I'm attaching InstallFSUIPC7 Now I'll try version 7.5.3 InstallFSUIPC7.log
John Dowson Posted October 28 Report Posted October 28 Your install log looks fine - no errors or issues. There is one thing that could be causing these issues - you are running FSUIPC7 with elevated privileges from the log file you attached earlier: Quote ********* FSUIPC7, Version 7.5.4 (13th July 2025) by John Dowson ********* WebSocket server found: C:\FSUIPC7\\Utils\FSUIPCWebSocketServer.exe Windows 11 detected - setting DisableMSFSMonitor to 'Enum' Windows 10 Pro 64 Bit reported as Build 26100, Release ID: 2009 (OS 10.0) FSUIPC is running with elevated privileges Reading options from "C:\FSUIPC7\FSUIPC7.ini" ... Why are you running with elevated privileges? If you run FSUIPC7 with elevated privileges, then you must also run your java program (and all FSUIPC client programs) at the same privilege level, otherwise it won't connect. Are you dong this? And are you also running MSFS with elevated privileges, and if so, why? If MSFS is not running with elevated privileges, then it won't be able to auto-start FSUIPC7 if that is set to run with elevated privileges. If you have set the FSUIPC7.exe to be ran with elevated privileges, remove this. If you ran the FSUIPC7 installer as admin (i.e. with elevated privileges), then uninstall, and then re-install as a standard user. The installer will request the privileges it needs which you need to approve, but it should not be ran as admin. John
IN7504 Posted October 28 Author Report Posted October 28 Yessssss Thanks a lot John, I changed the privileges of both Fsuipc and Js connect and now it works!!! 🤩
Ferran-Gonzalez Posted Sunday at 07:44 PM Report Posted Sunday at 07:44 PM Hello everyone, I’ve been experiencing a similar issue since yesterday, November 1st, 2025. Interestingly, it coincided with the latest Microsoft Flight Simulator 2020 update, although I don’t think that’s the cause, since I’ve asked other users and they’re not having the same problem. In my case, even though FSUIPC is open and connected to the simulator, addons such as Talking Flight Monitor or Flight Simulator First Officer do not detect it. I have to manually disconnect and reconnect FSUIPC to the simulator, and then everything starts working correctly again. However, in MSFS 2024, everything works perfectly fine. I’ve already reinstalled FSUIPC three or four times, but the issue persists. Up until now, it had always worked flawlessly. Just to clarify, everything I’m using is fully updated to the latest version. Thank you very much in advance for your help. Best regards, Ferran
John Dowson Posted Monday at 08:54 AM Report Posted Monday at 08:54 AM 13 hours ago, Ferran-Gonzalez said: In my case, even though FSUIPC is open and connected to the simulator, addons such as Talking Flight Monitor or Flight Simulator First Officer do not detect it. Can you activate logging for IPC Reads and show me a log file for this. Start everything as normal, and when the client programs cannot connect, disconnect and re-connect so that they connect, then exit FSUIPC7 and show me / attach your FSUIPC7.log file. John
Ferran-Gonzalez Posted Monday at 03:31 PM Report Posted Monday at 03:31 PM Okey, this is the log file FSUIPC7.log
John Dowson Posted Monday at 03:45 PM Report Posted Monday at 03:45 PM 1 minute ago, Ferran-Gonzalez said: this is the log file You did not activate the requested logging option for IPC Reads. However, your log file does show some connection issues: Quote 719 Auto-started via EXE.xml with DetectToConnectDelayAuto=50, InitialStallTime=15 3656 Simulator detected 53656 Trying to connect... 68656 **** SimConnect open event not received in required time limit: Re-connecting now... 68875 Trying to connect... 83875 **** SimConnect open event not received in required time limit: Re-connecting now... 84078 Trying to connect... 407125 === AI slots deleted! 410500 Trying to connect... It also looks like you disconnected and reconnect before FSUIPC had established a connection with MSFS2020...I didn't think this was even possible! And I do not understand why the connection attempt at 84078 didn't time out after 15 seconds. For this connection issue, you need to increase the DetectToConnectDelayAuto ini parameter (in your FSUIPC7.ini file). I am not sure wht value you should use - you need to time the period between when you see the FSUIPC7 splash screen to when MSFS2020 arrives at the main menu, and then set the value for that ini parameter to this. Please see the following FAQ entry on this connection issue: Note that this parameter will also be used when running MSFS2024 if you are using the same FSUIPC7 installation for both simulators. Once you have configured this parameter correctly (and for use with both MSFS2020 and MSFS2024 if using the same FSUIPC7 installation for both), you should set the ini parameter StartUpTuningDoneVersion to -1, which will disable the auto-tuning of this parameter by FSUIPC7 itself. John
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