Type Error - Fetch failed

[thepige]

Hi there,

I'm getting this issue when installing the extension.

I tried to search around on Google and Reddit to fix the problem but I'm afraid I'm not savvy enough with VSCode to understand where the trouble lies.

Anything I can do to change this?

Thanks,

[Heliozoa]

Hi,
We just released a new version 3.1.1 which has improved error messages. Can you try again and see what the error is? (Make sure to go to the settings first and set the Log Level to verbose)

[thepige]

Hi,

here's the error I'm getting now with 3.1.1 :

[Heliozoa]

The extension isn't able to connect to our server for some reason. Can you access the URL in the logs in your browser? Are you using a proxy of some kind?

One possible temporary solution you can try is to download the executable manually and place it in the path in the error message.

[AzzyTheTarned]

Having a similar issue. My organization forces all connections to go through a proxy, and system proxy is set in the windows settings. I managed, for example, to make loading extension list to load and download only by setting http_proxy parameter to my proxy address, however TMC gets stuck and throws this error:

[2025-10-13 03:42:22:840] [INFO] Starting moocfi.test-my-code in "production" mode.
[2025-10-13 03:42:22:840] [INFO] Visual Studio Code version: 1.104.3
[2025-10-13 03:42:22:840] [INFO] moocfi.test-my-code version: 3.5.0
[2025-10-13 03:42:22:840] [INFO] Currently open workspace: dev
[2025-10-13 03:42:22:840] [INFO] Platform win32 Arch x64
[2025-10-13 03:42:22:840] [INFO] TMC-Langs version: tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe
[2025-10-13 03:42:22:844] [INFO] Downloading TMC-langs from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe to temporary file c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\temp-tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe
[2025-10-13 03:42:34:038] [ERROR] TypeError: fetch failed. ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms).

TypeError: fetch failed
at e.exports.fetch (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:418751)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async t.downloadFile (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:537588)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243966

[2025-10-13 03:42:34:039] [ERROR] An error occurred while downloading TMC-langs:
Connection Error: fetch failed. Caused by: {ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms).

ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms)
at onConnectTimeout (node:internal/deps/undici/undici:2602:28)
at Immediate._onImmediate (node:internal/deps/undici/undici:2568:35)
at process.processImmediate (node:internal/timers:485:21)
}.

TypeError: fetch failed
at e.exports.fetch (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:418751)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async t.downloadFile (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:537588)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243966

[2025-10-13 03:42:34:039] [ERROR] Initialization error during tmc-langs setup:
Connection Error: fetch failed. Caused by: {ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms).

ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms)
at onConnectTimeout (node:internal/deps/undici/undici:2602:28)
at Immediate._onImmediate (node:internal/deps/undici/undici:2568:35)
at process.processImmediate (node:internal/timers:485:21)
}.

TypeError: fetch failed
at e.exports.fetch (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:418751)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async t.downloadFile (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:537588)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243966

If this issue is not resolved, the extension may not function properly.
[2025-10-13 03:42:34:039] [WARN] Could not check login status
[2025-10-13 03:42:34:043] [WARN] Skipped data migration
[2025-10-13 03:42:34:043] [WARN] Skipped tmc data directory check
[2025-10-13 03:42:34:045] [WARN] Skipped login command setup
[2025-10-13 03:42:34:046] [WARN] Failed to set initial exercises.
Error: Extension was not initialized properly.

Downloading the .exe file directly with browser works, but trying again with the file put in the cli directory immediately leads me to this error:

[2025-10-13 04:10:45:381] [INFO] Starting moocfi.test-my-code in "production" mode.
[2025-10-13 04:10:45:381] [INFO] Visual Studio Code version: 1.104.3
[2025-10-13 04:10:45:381] [INFO] moocfi.test-my-code version: 3.5.0
[2025-10-13 04:10:45:381] [INFO] Currently open workspace: dev
[2025-10-13 04:10:45:381] [INFO] Platform win32 Arch x64
[2025-10-13 04:10:45:382] [INFO] TMC-Langs version: tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe
[2025-10-13 04:10:45:702] [ERROR] Fatal error during initialization:
Error: ENOENT: no such file or directory, open 'c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256'.

Error: ENOENT: no such file or directory, open 'c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256'
at Object.readFileSync (node:fs:442:20)
at t.readFileSync (node:electron/js2c/node_init:2:11013)
at t.ensureLangsUpdated (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243310)
at c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\extension.js:1:1516
at r.activate (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\extension.js:1:5451)
at $y.kb (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:116:15342)
at $y.jb (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:116:15087)
at file:///c:/Users/xxxv/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:116:13245
at async _b.n (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13382)
at async _b.m (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13345)
at async _b.l (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:12801)

I figured maybe i could download the sha256 file directly too, and i did. Putting the file to the directory as well triggers hash mismatch and leads to redownloading and failing miserably. The logs are:

[2025-10-13 04:15:38:174] [INFO] Starting moocfi.test-my-code in "production" mode.
[2025-10-13 04:15:38:174] [INFO] Visual Studio Code version: 1.104.3
[2025-10-13 04:15:38:174] [INFO] moocfi.test-my-code version: 3.5.0
[2025-10-13 04:15:38:174] [INFO] Currently open workspace: dev
[2025-10-13 04:15:38:175] [INFO] Platform win32 Arch x64
[2025-10-13 04:15:38:175] [INFO] TMC-Langs version: tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe
[2025-10-13 04:15:38:485] [ERROR] Mismatch between CLI and checksum, trying redownload
[2025-10-13 04:15:38:495] [INFO] Downloading TMC-langs from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe to temporary file c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\temp-tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe
[2025-10-13 04:15:49:338] [ERROR] TypeError: fetch failed. ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms).

TypeError: fetch failed
at e.exports.fetch (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:418751)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async t.downloadFile (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:537588)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243966

[2025-10-13 04:15:49:338] [ERROR] An error occurred while downloading TMC-langs:
Connection Error: fetch failed. Caused by: {ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms).

ConnectTimeoutError: Connect Timeout Error (attempted address: download.mooc.fi:443, timeout: 10000ms)
at onConnectTimeout (node:internal/deps/undici/undici:2602:28)
at Immediate._onImmediate (node:internal/deps/undici/undici:2568:35)
at process.processImmediate (node:internal/timers:485:21)
}.

TypeError: fetch failed
at e.exports.fetch (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:418751)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async t.downloadFile (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:537588)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243966

[2025-10-13 04:15:49:339] [ERROR] Initialization error during tmc-langs setup:
Error: Mismatch found between CLI (01255ce1b946b0c89d65153ed8e9838c87d11e0d34636f3506a57ac844d29601 c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe) and checksum (01255CE1B946B0C89D65153ED8E9838C87D11E0D34636F3506A57AC844D29601
c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256 from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256).

Error: Mismatch found between CLI (01255ce1b946b0c89d65153ed8e9838c87d11e0d34636f3506a57ac844d29601 c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe) and checksum (01255CE1B946B0C89D65153ED8E9838C87D11E0D34636F3506A57AC844D29601
c:\Users\xxx\AppData\Roaming\Code\User\globalStorage\moocfi.test-my-code\cli\tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256 from https://download.mooc.fi/tmc-langs-rust/tmc-langs-cli-x86_64-pc-windows-msvc-0.39.1.exe.sha256)
at t.ensureLangsUpdated (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\lib.js:2:243508)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
at async c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\extension.js:1:1508
at async r.activate (c:\Users\xxx.vscode\extensions\moocfi.test-my-code-3.5.0\dist\extension.js:1:1063)
at async _b.n (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13382)
at async _b.m (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13345)
at async _b.l (file:///c:/Users/xxx/AppData/Local/Programs/Microsoft%20VS%20Code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:12801)

If this issue is not resolved, the extension may not function properly.
[2025-10-13 04:15:49:339] [WARN] Could not check login status
[2025-10-13 04:15:49:344] [WARN] Skipped data migration
[2025-10-13 04:15:49:344] [WARN] Skipped tmc data directory check
[2025-10-13 04:15:49:345] [WARN] Skipped login command setup
[2025-10-13 04:15:49:346] [WARN] Failed to set initial exercises.
Error: Extension was not initialized properly.

Lowercasing all characters in the sha256 file doesn't work too and brings the same error, even though the hashes are literally identical.
Maybe there is a way to make it work manually somehow?