I'm currently migrating my PC from W10 to W11. I've reinstalled IDE 2.3.8 no problem seemed to appear, but at start the IDE stays with logo pulsing indefinitively.
I tried in many ways to reboot, desinstall reinstall and so on, but I got the same result.
Could you help me to solve this isue.
Hi @sergio83100. I'm going to ask you to provide some additional information that might help us to identify the problem.
This procedure is not intended to solve the problem. The purpose is to gather more information.
Please do this:
C:\Program Files\Arduino IDE
C:\Users\<username>\AppData\Local\Programs\Arduino IDE
<username> is your Windows username) If looking for it with your file manager or command line, note that the AppData folder is hidden by default. On Windows "File Explorer", you can make it visible by opening the "View" menu, then checking the box next to "☐ Hidden items".& ".\Arduino IDE"
<CODE/> icon on the post composer toolbar.```) to your reply to make sure the error messages are correctly formatted.Please let us know if you have any questions or problems while following those instructions.
Hi ptillisch,
Thanks to you to reply me.
I've done what you asked me. So look at result:
Windows PowerShell
Copyright (C) Microsoft Corporation. Tous droits réservés.
Installez la dernière version de PowerShell pour de nouvelles fonctionnalités et améliorations !
PS C:\Users\Serge\AppData\Local\Programs\Arduino IDE> ".\Arduino IDE"
.\Arduino IDE
PS C:\Users\Serge\AppData\Local\Programs\Arduino IDE>
Except if I made a mistake, the result is quiet a surprise: no message was displayed
Cordialy
You forgot the & part of the command. Please try it again, but this time type the command exactly as I wrote it in my instructions:
Sorry for my mistake ...
With the right command it sounds better:
PS C:\Users\Serge\AppData\Local\Programs\Arduino IDE> & ".\Arduino IDE"
PS C:\Users\Serge\AppData\Local\Programs\Arduino IDE>
Arduino IDE 2.3.8
Checking for frontend application configuration customizations. Module path: C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\electron-main.js, destination 'package.json': C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\package.json
Setting 'theia.frontend.config.appVersion' application configuration value to: "2.3.8" (type of string)
Setting 'theia.frontend.config.cliVersion' application configuration value to: "1.4.1" (type of string)
Setting 'theia.frontend.config.buildDate' application configuration value to: "2026-02-25T15:38:21.789Z" (type of string)
Frontend application configuration after modifications: {"applicationName":"Arduino IDE","defaultTheme":{"light":"arduino-theme","dark":"arduino-theme-dark"},"defaultIconTheme":"none","electron":{"windowOptions":{},"showWindowEarly":true,"splashScreenOptions":{},"uriScheme":"arduino-ide"},"defaultLocale":"","validatePreferencesSchema":false,"reloadOnReconnect":true,"uriScheme":"theia","preferences":{"window.title":"${rootName}${activeEditorShort}${appName}","files.autoSave":"afterDelay","editor.minimap.enabled":false,"editor.tabSize":2,"editor.scrollBeyondLastLine":false,"editor.quickSuggestions":{"other":false,"comments":false,"strings":false},"editor.maxTokenizationLineLength":500,"editor.bracketPairColorization.enabled":false,"breadcrumbs.enabled":false,"workbench.tree.renderIndentGuides":"none","explorer.compactFolders":false},"appVersion":"2.3.8","cliVersion":"1.4.1","buildDate":"2026-02-25T15:38:21.789Z"}
Starting backend process. PID: 15036
Showing main window early
Using browser-only version of superagent in non-browser environment
Configuration directory URI: 'file:///c%3A/Users/Serge/.arduinoIDE'
Configuring to accept webviews on '^.+\.webview\..+$' hostname.
2026-05-12T13:42:57.206Z root WARN Backend u.initialize took longer than the expected maximum 50 milliseconds: 99.1 ms [Finished 2.940 s after backend start]
2026-05-12T13:42:57.212Z root WARN Backend Object.initialize took longer than the expected maximum 50 milliseconds: 94.8 ms [Finished 2.940 s after backend start]
2026-05-12T13:42:57.213Z root INFO Backend a.initialize: 3.6 ms [Finished 2.940 s after backend start]
2026-05-12T13:42:57.213Z root INFO Backend a.initialize: 3.1 ms [Finished 2.940 s after backend start]
2026-05-12T13:42:57.213Z root INFO Backend u.initialize: 4.4 ms [Finished 2.942 s after backend start]
2026-05-12T13:42:57.218Z root WARN Backend l.initialize took longer than the expected maximum 50 milliseconds: 99.4 ms [Finished 2.945 s after backend start]
2026-05-12T13:42:57.241Z root INFO configured all backend app contributions
2026-05-12T13:42:57.243Z root INFO Backend l.onStart: 4.1 ms [Finished 2.981 s after backend start]
2026-05-12T13:42:57.244Z root INFO Backend d.onStart: 0.3 ms [Finished 2.981 s after backend start]
2026-05-12T13:42:57.247Z root INFO Backend a.onStart: 1.0 ms [Finished 2.982 s after backend start]
2026-05-12T13:42:57.247Z config INFO >>> Initializing CLI configuration...
2026-05-12T13:42:57.248Z root INFO Backend x.onStart: 1.3 ms [Finished 2.984 s after backend start]
2026-05-12T13:42:57.248Z config INFO Loading CLI configuration from c:\Users\Serge\.arduinoIDE\arduino-cli.yaml...
2026-05-12T13:42:57.248Z daemon INFO Starting daemon from C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\resources\arduino-cli.exe...
2026-05-12T13:42:57.248Z root INFO Backend w.onStart: 1.5 ms [Finished 2.986 s after backend start]
2026-05-12T13:42:57.248Z discovery-log INFO start
2026-05-12T13:42:57.248Z discovery-log INFO start new deferred
2026-05-12T13:42:57.248Z root INFO Backend v.onStart: 0.8 ms [Finished 2.987 s after backend start]
2026-05-12T13:42:57.248Z root INFO Backend a.onStart: 0.3 ms [Finished 2.988 s after backend start]
2026-05-12T13:43:17.320Z root WARN The local plugin referenced by local-dir:/c%3A/Users/Serge/.arduinoIDE/plugins does not exist.
2026-05-12T13:43:17.320Z root WARN The local plugin referenced by local-dir:/c%3A/Users/Serge/.arduinoIDE/deployedPlugins does not exist.
2026-05-12T13:43:17.321Z root WARN The local plugin referenced by local-dir:C:\Users\Serge\.arduinoIDE\plugins does not exist.
2026-05-12T13:43:24.616Z root INFO Theia app listening on http://127.0.0.1:63354.
2026-05-12T13:43:24.617Z root INFO Finished starting backend application: 27368.0 ms [Finished 30.356 s after backend start]
[11448:0512/144344.401:ERROR:network_service_instance_impl.cc(599)] Network service crashed, restarting service.
2026-05-12T13:44:17.779Z config INFO Loaded CLI configuration: {"board_manager":{"additional_urls":[]}}
2026-05-12T13:44:17.779Z config INFO Loading fallback CLI configuration to get 'directories.data' and 'directories.user'
2026-05-12T13:44:17.891Z daemon INFO time="2026-05-12T14:44:00+01:00" level=info msg="arduino-cli version 1.4.1"
time="2026-05-12T14:44:00+01:00" level=info msg="Using config file: c:\\Users\\Serge\\.arduinoIDE\\arduino-cli.yaml"
time="2026-05-12T14:44:00+01:00" level=info msg="Executing `arduino-cli daemon`"
Daemon is now listening on 127.0.0.1:63355
{"IP":"127.0.0.1","Port":"63355"}
2026-05-12T13:44:17.891Z daemon INFO Daemon is running.
2026-05-12T13:44:18.235Z root INFO Resolve plugins list: 80990.5 ms [Finished 83.983 s after backend start]
2026-05-12T13:44:21.216Z root INFO Deploy plugins list: 83973.1 ms [Finished 86.966 s after backend start]
2026-05-12T13:44:38.005Z root ERROR Uncaught Exception: Error: 14 UNAVAILABLE: No connection established. Last error: Error: connect ETIMEDOUT 127.0.0.1:63355
2026-05-12T13:44:38.005Z root ERROR Error: 14 UNAVAILABLE: No connection established. Last error: Error: connect ETIMEDOUT 127.0.0.1:63355
at t.callErrorFromStatus (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:3120831)
at Object.onReceiveStatus (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6717214)
at Object.onReceiveStatus (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:2604592)
at Object.onReceiveStatus (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:2604037)
at C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:4347314
at process.processTicksAndRejections (node:internal/process/task_queues:77:11)
for call at
at s.makeUnaryRequest (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6716745)
at s.create (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:3119924)
at instance (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6322922)
at new Promise (<anonymous>)
at y.createClient (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6322899)
at y.create (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6321807)
at C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6320703
at C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:1050849
at s.invoke (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:1050939)
at a.fire (C:\Users\Serge\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:1052742)
2026-05-12T13:44:44.057Z config INFO Loaded fallback CLI configuration: {"directories":{"user":"C:\\Users\\Serge\\Documents\\Arduino","data":"C:\\Users\\Serge\\AppData\\Local\\Arduino15"}}
2026-05-12T13:44:44.057Z config INFO Merged CLI configuration with the fallback: {"directories":{"user":"C:\\Users\\Serge\\Documents\\Arduino","data":"C:\\Users\\Serge\\AppData\\Local\\Arduino15"},"board_manager":{"additional_urls":[]}}
2026-05-12T13:44:44.057Z config INFO Loaded the CLI configuration.
2026-05-12T13:44:44.059Z config INFO Mapped the CLI configuration: {"dataDirUri":"file:///c%3A/Users/Serge/AppData/Local/Arduino15","sketchDirUri":"file:///c%3A/Users/Serge/Documents/Arduino","additionalUrls":[],"network":"none","locale":"en"}
2026-05-12T13:44:44.059Z config INFO Validating the CLI configuration...
2026-05-12T13:44:44.060Z config INFO The CLI config is valid.
2026-05-12T13:44:44.060Z config INFO <<< Initialized the CLI configuration.
Hi @sergio83100 ,
while waiting you may post the log file to an AI, e.g. Gemini to get some hints. I did and got an answer too lengthy to post here...
No guarantee but probably worth a try...
Good luck!
ec2021
Hi ec2021,
Thanks for your help!
I've posted the powershell log to Gemini and I got a reply with some new elements.
I'll push my investigation further and let you now.
Hi again ec2021 and ptillisch,
After analyzing the Gemini scan, I've concluded that the IDE startup problem is due to my antivirus firewall. This clears the IDE.
Now the ball is in my court!
Thanks again for your help.
I'm closing the thread.
[solved]
You might keep the thread open until you are sure it's solved ...
I personally trust Per more than any AI ...
Humans are still much better than AI in anticipating what one really means and requires.
But I'm also glad if the hint was of assistance!
Bonne chance!
ec2021
Of course, AI can only be considered a supplement; I don't think it will ever replace human neural networks because it is a product of them.
In this instance, it helped me. By disabling my firewall, the Arduino IDE was able to start.
To be honest, this is the first time I've used AI. After that, you have to interpret it; it's like a cooking recipe. If you're not a cooker, it can lead to disaster for your guests!
But honestly, I think the problem isn't related to the IDE itself, but to my firewall settings.
Many thanks again for your help !!!
I share your thoughts about the interpretation and verification of AI responses.
Finally it's statistics.
The results highly depend on the quality of the input (ambiguity versus clarity) and the statistically "knowledge" basis. If there's a lot of wrong or misleading content found in the internet it will come up with crap as well.
But we can sort out most garbage by giving corrective requests.
Again, I'm glad you were able to sort it out.
Thanks for your vote of confidence.
The relevant part of the logs:
This does make me think that the problem is something to do with @sergio83100's local network.
Arduino IDE communicates with some of its software components via an internal TCP/IP port in your computer on "localhost".
The error message is showing that this communication failed (127.0.0.1 is the localhost IP address). The function of Arduino IDE is dependent on being able to communicate with those "backend" software components, so if this communication fails it puts the IDE into a state where it can't even start up fully.
This is a different situation than the case where Arduino IDE is failing to download some files from the Internet. In that case, we would also need to consider whether the failure was caused by some external network system. However, the localhost communication is internal to the computer, so this would indicate that the problem is with @sergio83100's system itself.
Unfortunately I don't have any ideas about the path forward for investigating and resolving the problem. I did find one report from a user who encountered the same problem and found an odd workaround:
Hi Per,
you demonstrated one of the main differences of AI answers and human response:
Unfortunately I don't have any ideas about the path forward for investigating and resolving the problem.
An AI would almost never post that honest answer