Arduino IDE stuck loading

bonelesssugar · May 18, 2025, 6:24pm

I just installed Arduino IDE 2.3.6 for the first time and it refuses to actually load past the pulsing Arduino icon. Here is the powershell:

Arduino IDE 2.3.6
Checking for frontend application configuration customizations. Module path: C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\electron-main.js, destination 'package.json': C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\package.json
Setting 'theia.frontend.config.appVersion' application configuration value to: "2.3.6" (type of string)
Setting 'theia.frontend.config.cliVersion' application configuration value to: "1.2.0" (type of string)
Setting 'theia.frontend.config.buildDate' application configuration value to: "2025-04-09T11:26:55.498Z" (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}${appName}","files.autoSave":"afterDelay","editor.minimap.enabled":false,"editor.tabSize":2,"editor.scrollBeyondLastLine":false,"editor.quickSuggestions":{"other":false,"comments":false,"strings":false},"editor.maxTokenizationLineLength":500,"editor.bracketPairColorization.enabled":false,"breadcrumbs.enabled":false,"workbench.tree.renderIndentGuides":"none","explorer.compactFolders":false},"appVersion":"2.3.6","cliVersion":"1.2.0","buildDate":"2025-04-09T11:26:55.498Z"}
Starting backend process. PID: 17952
Showing main window early
Using browser-only version of superagent in non-browser environment
Configuration directory URI: 'file:///c%3A/Users/obeli/.arduinoIDE'
Configuring to accept webviews on '^.+\.webview\..+$' hostname.
2025-05-18T18:12:43.416Z root INFO Backend u.initialize: 23.3 ms [Finished 0.482 s after backend start]
2025-05-18T18:12:43.417Z root INFO Backend Object.initialize: 21.2 ms [Finished 0.482 s after backend start]
2025-05-18T18:12:43.417Z root INFO Backend a.initialize: 1.4 ms [Finished 0.482 s after backend start]
2025-05-18T18:12:43.417Z root INFO Backend a.initialize: 1.2 ms [Finished 0.482 s after backend start]
2025-05-18T18:12:43.417Z root INFO Backend u.initialize: 1.6 ms [Finished 0.483 s after backend start]
2025-05-18T18:12:43.419Z root INFO Backend l.initialize: 22.5 ms [Finished 0.484 s after backend start]
2025-05-18T18:12:43.424Z root INFO configured all backend app contributions
2025-05-18T18:12:43.424Z root INFO Backend l.onStart: 0.9 ms [Finished 0.492 s after backend start]
2025-05-18T18:12:43.425Z root INFO Backend d.onStart: 0.1 ms [Finished 0.492 s after backend start]
2025-05-18T18:12:43.425Z root INFO Backend a.onStart: 0.3 ms [Finished 0.493 s after backend start]
2025-05-18T18:12:43.426Z config INFO >>> Initializing CLI configuration...
2025-05-18T18:12:43.426Z root INFO Backend x.onStart: 0.4 ms [Finished 0.493 s after backend start]
2025-05-18T18:12:43.426Z config INFO Loading CLI configuration from c:\Users\obeli\.arduinoIDE\arduino-cli.yaml...
2025-05-18T18:12:43.426Z daemon INFO Starting daemon from C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\resources\arduino-cli.exe...
2025-05-18T18:12:43.426Z root INFO Backend w.onStart: 0.4 ms [Finished 0.494 s after backend start]
2025-05-18T18:12:43.426Z discovery-log INFO start
2025-05-18T18:12:43.426Z discovery-log INFO start new deferred
2025-05-18T18:12:43.426Z root INFO Backend v.onStart: 0.2 ms [Finished 0.494 s after backend start]
2025-05-18T18:12:43.426Z root INFO Backend a.onStart: 0.1 ms [Finished 0.494 s after backend start]
2025-05-18T18:12:43.438Z root INFO Theia app listening on http://127.0.0.1:50804.
2025-05-18T18:12:43.438Z root INFO Finished starting backend application: 12.1 ms [Finished 0.506 s after backend start]
2025-05-18T18:12:43.439Z root WARN The local plugin referenced by local-dir:/c%3A/Users/obeli/.arduinoIDE/plugins does not exist.
2025-05-18T18:12:43.439Z root WARN The local plugin referenced by local-dir:/c%3A/Users/obeli/.arduinoIDE/deployedPlugins does not exist.
2025-05-18T18:12:43.439Z root WARN The local plugin referenced by local-dir:C:\Users\obeli\.arduinoIDE\plugins does not exist.
2025-05-18T18:12:43.457Z config INFO Loaded CLI configuration: {"board_manager":{"additional_urls":[]}}
2025-05-18T18:12:43.457Z config INFO Loading fallback CLI configuration to get 'directories.data' and 'directories.user'
2025-05-18T18:12:43.502Z root INFO Resolve plugins list: 74.4 ms [Finished 0.570 s after backend start]
2025-05-18T18:12:43.510Z daemon INFO time="2025-05-18T14:12:43-04:00" level=info msg="arduino-cli version 1.2.0"
2025-05-18T18:12:43.526Z daemon INFO time="2025-05-18T14:12:43-04:00" level=info msg="Using config file: c:\\Users\\obeli\\.arduinoIDE\\arduino-cli.yaml"
time="2025-05-18T14:12:43-04:00" level=info msg="Executing `arduino-cli daemon`"
Daemon is now listening on 127.0.0.1:50805
{"IP":"127.0.0.1","Port":"50805"}
2025-05-18T18:12:43.526Z daemon INFO Daemon is running.
2025-05-18T18:12:43.538Z config INFO Loaded fallback CLI configuration: {"directories":{"user":"C:\\Users\\obeli\\Documents\\Arduino","data":"C:\\Users\\obeli\\AppData\\Local\\Arduino15"}}
2025-05-18T18:12:43.538Z config INFO Merged CLI configuration with the fallback: {"directories":{"user":"C:\\Users\\obeli\\Documents\\Arduino","data":"C:\\Users\\obeli\\AppData\\Local\\Arduino15"},"board_manager":{"additional_urls":[]}}
2025-05-18T18:12:43.538Z config INFO Loaded the CLI configuration.
2025-05-18T18:12:43.542Z config INFO Mapped the CLI configuration: {"dataDirUri":"file:///c%3A/Users/obeli/AppData/Local/Arduino15","sketchDirUri":"file:///c%3A/Users/obeli/Documents/Arduino","additionalUrls":[],"network":"none","locale":"en"}
2025-05-18T18:12:43.542Z config INFO Validating the CLI configuration...
2025-05-18T18:12:43.548Z config INFO The CLI config is valid.
2025-05-18T18:12:43.548Z config INFO <<< Initialized the CLI configuration.
2025-05-18T18:12:43.554Z daemon INFO time="2025-05-18T14:12:43-04:00" level=info msg="Starting download" url="https://downloads.arduino.cc/libraries/library_index.tar.bz2"
2025-05-18T18:12:43.908Z root INFO Deploy plugins list: 481.4 ms [Finished 0.977 s after backend start]
2025-05-18T18:12:44.585Z root INFO creating connection for 1
2025-05-18T18:12:45.257Z root WARN A command editor.action.toggleStickyScroll is already registered.
Opening channel for service path '/services/electron-window'.
Opening channel for service path '/services/ide-updater'.
2025-05-18T18:12:45.335Z root INFO Start frontend contributions: 233.9 ms [Finished 1.875 s after frontend start]
2025-05-18T18:12:45.335Z root INFO Changed application state from 'init' to 'started_contributions'.
2025-05-18T18:12:45.343Z root INFO Changed application state from 'started_contributions' to 'attached_shell'.
2025-05-18T18:12:45.343Z root INFO >>> Restoring the layout state...
2025-05-18T18:12:45.372Z root INFO [3579aa52-486b-48a6-880e-95851caf7089] Waiting for backend deployment: 50.2 ms [Finished 1.921 s after frontend start]
2025-05-18T18:12:45.862Z root INFO [hosted-plugin: 4792] PLUGIN_HOST(4792) starting instance
[Object: null prototype] {}
2025-05-18T18:12:46.322Z root INFO [3579aa52-486b-48a6-880e-95851caf7089] Sync of 23 plugins: 954.0 ms [Finished 2.875 s after frontend start]
2025-05-18T18:13:43.560Z root ERROR Detected an error response during the gRPC core client initialization: code: 3, message: Error downloading index 'https://downloads.arduino.cc/libraries/library_index.tar.bz2': Get "https://downloads.arduino.cc/libraries/library_index.tar.bz2": net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
2025-05-18T18:13:43.561Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Loading index file: loading json index file C:\Users\obeli\AppData\Local\Arduino15\package_index.json: open C:\Users\obeli\AppData\Local\Arduino15\package_index.json: The system cannot find the file specified.
2025-05-18T18:13:43.561Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not found
2025-05-18T18:13:43.561Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not found
2025-05-18T18:13:43.561Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Loading index file: reading library_index.json: open C:\Users\obeli\AppData\Local\Arduino15\library_index.json: The system cannot find the file specified.
2025-05-18T18:13:43.566Z root ERROR The primary packages indexes are missing. Running indexes update before initializing the core gRPC client The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Loading index file: loading json index file C:\Users\obeli\AppData\Local\Arduino15\package_index.json: open C:\Users\obeli\AppData\Local\Arduino15\package_index.json: The system cannot find the file specified.
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not found
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not found
[library-index] - code: 9, message: Loading index file: reading library_index.json: open C:\Users\obeli\AppData\Local\Arduino15\library_index.json: The system cannot find the file specified.

2025-05-18T18:13:43.566Z daemon INFO time="2025-05-18T14:13:43-04:00" level=info msg="Loading hardware from: C:\\Users\\obeli\\AppData\\Local\\Arduino15\\packages"
time="2025-05-18T14:13:43-04:00" level=info msg="Loading libraries index file" index="C:\\Users\\obeli\\AppData\\Local\\Arduino15\\library_index.json"
time="2025-05-18T14:13:43-04:00" level=info msg="Adding libraries dir" dir="C:\\Users\\obeli\\AppData\\Local\\Arduino15\\libraries" isSingleLibrary=false location=ide
time="2025-05-18T14:13:43-04:00" level=info msg="Adding libraries dir" dir="C:\\Users\\obeli\\Documents\\Arduino\\libraries" isSingleLibrary=false location=user
2025-05-18T18:13:43.567Z daemon INFO time="2025-05-18T14:13:43-04:00" level=info msg="Updating index" url="https://downloads.arduino.cc/packages/package_index.tar.bz2"
2025-05-18T18:13:43.568Z daemon INFO time="2025-05-18T14:13:43-04:00" level=info msg="Starting download" url="https://downloads.arduino.cc/libraries/library_index.tar.bz2"
2025-05-18T18:13:43.569Z root INFO core-client-provider [library-index] Downloading index: library_index.tar.bz2

2025-05-18T18:13:43.570Z root INFO core-client-provider [platform-index] Downloading index: package_index.tar.bz2

2025-05-18T18:13:43.570Z daemon INFO time="2025-05-18T14:13:43-04:00" level=info msg="Starting download" url="https://downloads.arduino.cc/packages/package_index.tar.bz2"
2025-05-18T18:14:43.580Z root ERROR Failed to update platform, library indexes. Error: 13 INTERNAL: Error downloading index 'https://downloads.arduino.cc/libraries/library_index.tar.bz2': Get "https://downloads.arduino.cc/libraries/library_index.tar.bz2": net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
    at t.callErrorFromStatus (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:3089094)
    at Object.onReceiveStatus (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6681994)
    at Object.onReceiveStatus (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:2571739)
    at C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:4307911
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11)
for call at
    at s.makeServerStreamRequest (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6681761)
    at s.updateLibrariesIndex (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:3088187)
    at C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6284984
    at C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6285177
    at new Promise (<anonymous>)
    at y.doUpdateIndex (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6285156)
    at y.updateLibraryIndex (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6284956)
    at y.updateIndex (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6284230)
    at y.initInstanceWithFallback (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6282462)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
2025-05-18T18:14:43.582Z daemon INFO time="2025-05-18T14:14:43-04:00" level=info msg="Starting download" url="https://downloads.arduino.cc/libraries/library_index.tar.bz2"
2025-05-18T18:15:43.592Z root ERROR Detected an error response during the gRPC core client initialization: code: 3, message: Error downloading index 'https://downloads.arduino.cc/libraries/library_index.tar.bz2': Get "https://downloads.arduino.cc/libraries/library_index.tar.bz2": net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)
2025-05-18T18:15:43.592Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Loading index file: loading json index file C:\Users\obeli\AppData\Local\Arduino15\package_index.json: open C:\Users\obeli\AppData\Local\Arduino15\package_index.json: The system cannot find the file specified.
2025-05-18T18:15:43.592Z daemon INFO time="2025-05-18T14:15:43-04:00" level=info msg="Loading hardware from: C:\\Users\\obeli\\AppData\\Local\\Arduino15\\packages"
time="2025-05-18T14:15:43-04:00" level=info msg="Loading libraries index file" index="C:\\Users\\obeli\\AppData\\Local\\Arduino15\\library_index.json"
2025-05-18T18:15:43.593Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not found
2025-05-18T18:15:43.593Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not found
2025-05-18T18:15:43.593Z root ERROR Detected an error response during the gRPC core client initialization: code: 9, message: Loading index file: reading library_index.json: open C:\Users\obeli\AppData\Local\Arduino15\library_index.json: The system cannot find the file specified.
2025-05-18T18:15:43.594Z root ERROR Uncaught Exception:  Error: The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Loading index file: loading json index file C:\Users\obeli\AppData\Local\Arduino15\package_index.json: open C:\Users\obeli\AppData\Local\Arduino15\package_index.json: The system cannot find the file specified.
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not found
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not found
[library-index] - code: 9, message: Loading index file: reading library_index.json: open C:\Users\obeli\AppData\Local\Arduino15\library_index.json: The system cannot find the file specified.

2025-05-18T18:15:43.594Z root ERROR Error: The index of the cores and libraries must be updated before initializing the core gRPC client.
The following problems were detected during the gRPC client initialization:
[platform-index] - code: 9, message: Loading index file: loading json index file C:\Users\obeli\AppData\Local\Arduino15\package_index.json: open C:\Users\obeli\AppData\Local\Arduino15\package_index.json: The system cannot find the file specified.
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:serial-discovery not found
[platform-index] - code: 9, message: Error loading hardware platform: discovery builtin:mdns-discovery not found
[library-index] - code: 9, message: Loading index file: reading library_index.json: open C:\Users\obeli\AppData\Local\Arduino15\library_index.json: The system cannot find the file specified.

    at C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6283973
    at y.evaluateErrorStatus (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6283989)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async a.<anonymous> (C:\Users\obeli\AppData\Local\Programs\Arduino IDE\resources\app\lib\backend\main.js:2:6283659)
2025-05-18T18:15:43.594Z daemon INFO time="2025-05-18T14:15:43-04:00" level=info msg="Adding libraries dir" dir="C:\\Users\\obeli\\AppData\\Local\\Arduino15\\libraries" isSingleLibrary=false location=ide
time="2025-05-18T14:15:43-04:00" level=info msg="Adding libraries dir" dir="C:\\Users\\obeli\\Documents\\Arduino\\libraries" isSingleLibrary=false location=user

sonofcy · May 18, 2025, 7:08pm

Are you connected to the internet? Are you at home, work, school?

bonelesssugar · May 18, 2025, 7:14pm

I am connected to the internet, that's how I downloaded the installer. I am at work currently but was going to try again when I get home and was assuming that it'd be a firewall issue. Otherwise I was going to try deleting arduino-cli.yaml. I had installed it a month ago on a different drive at school and had no problems with it, but that was 2.3.5. Just wanted to make sure there wasn't something obvious I was missing.

sonofcy · May 18, 2025, 7:46pm

Not sure what deleting the yaml will do. Is it a laptop?

bonelesssugar · May 18, 2025, 8:34pm

Yeah, it's a laptop. I was basing it off of this thread:
https://forum.arduino.cc/t/not-able-to-open-arduino-ide/1245257/2

2.3.6 is working now on home wifi, thanks!

sonofcy · May 18, 2025, 8:45pm

Then it's got to do with the work internet environment. Once you complete the initial downloads (in the background), it may mostly work at work, but your network guy can look at his server logs to see what connection(s) are being blocked and deal with that.

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