Error map
NotFoundError: Requested device not found Console: NotFoundError: Requested device not found (getUserMedia has no camera or microphone)
Browser · layer 1, On your device
Centre: this error. First ring: errors it is linked with (7). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (7)
NotAllowedError: play() failed because the user didn't interact with the document first.
The browser blocked media autoplay with sound until the user interacts with the page.
Chrome: Aw, Snap! Something went wrong while displaying this webpage. Error code: STATUS_ACCESS_VIOLATION / SIGILL / Out of Memory
A Chrome tab crashed — out of memory, a faulty extension, a graphics/driver issue or a very heavy page.
Browser: This network requires you to sign in — captive portal (hotel, airport, café Wi-Fi) blocking HTTPS sites
The Wi-Fi needs a login or acceptance page first; until you complete it, secure sites fail with certificate or connection errors.
Console: NotAllowedError: Permission denied (getUserMedia — camera or microphone blocked)
The user (or the browser/OS/policy) denied camera or microphone access, so `navigator.mediaDevices.getUserMedia()` was rejected.
Console: NotReadableError: Could not start video source (camera in use by another app)
The camera or microphone exists but could not be opened — another application, tab or a driver problem holds it.
Console: Unchecked runtime.lastError: The message port closed before a response was received (extension message)
A browser extension sent or received a message and the other side closed the channel without replying — almost always an extensio…
Console: SecurityError: Failed to execute 'toDataURL' / 'getImageData' on 'HTMLCanvasElement': Tainted canvases may not be exported
You drew an image from another origin onto a canvas without CORS permission, so the browser blocks reading pixels back out.
Two steps away (18)
net::ERR_BLOCKED_BY_CLIENT
A browser extension (ad blocker, privacy tool) blocked the request.
net::ERR_CONNECTION_REFUSED (This site can't be reached — refused to connect)
The browser reached the host but nothing was listening on that port.
net::ERR_NAME_NOT_RESOLVED (This site can't be reached — server IP address could not be found)
DNS couldn’t resolve the hostname in the browser.
Blue Screen: MEMORY_MANAGEMENT (Stop code 0x0000001A)
Windows detected a severe memory-management error — commonly faulty RAM, unstable memory settings or a bad driver.
RangeError: Invalid array length
An array was created or resized with a negative, fractional or enormous length.
Chrome: This page isn’t working — sent an invalid response. ERR_CONTENT_DECODING_FAILED
The response claims to be compressed (gzip/brotli) but cannot be decompressed — it was double-compressed, truncated or not compre…
HTTP 407 Proxy Authentication Required
A proxy between you and the server requires credentials before it will forward your request.
HTTP 408 Request Timeout
The server closed the connection because the client took too long to send the complete request.
TypeError: Failed to fetch / NetworkError when attempting to fetch resource
The browser couldn’t complete the request at the network level — CORS, DNS, offline, blocked mixed content, or the server refused…
Console: User denied Geolocation / Only secure origins are allowed (geolocation) / GeolocationPositionError code 1
`navigator.geolocation` failed because the user blocked location, the page is not on HTTPS, or the OS has location services off.
Console: [Violation] Permissions policy violation: camera is not allowed in this document (Feature-Policy)
A browser feature (camera, microphone, geolocation, fullscreen, payment…) was blocked by a `Permissions-Policy` header or an ifra…
Blue screen: VIDEO_TDR_FAILURE (0x00000116) — nvlddmkm.sys / atikmpag.sys / igdkmd64.sys
The graphics driver stopped responding and Windows couldn’t reset it in time.
Chrome: Page Unresponsive — The following page(s) have become unresponsive. You can wait for them to become responsive or exit the page(s)
A tab is stuck in a busy loop or waiting on something heavy, so Chrome offers to wait or kill it.
Console: Uncaught (in promise) Error / TypeError / DOMException — unhandled promise rejection
A promise was rejected and no `.catch()` or `try/catch` handled it, so the browser logs it as an unhandled rejection.
Console: Failed to register a ServiceWorker: A bad HTTP response code (404) was received when fetching the script
The browser could not fetch, parse or install the service worker script, or the page is not allowed to register one (HTTPS and sc…
CORS Error: No 'Access-Control-Allow-Origin' header is present
The browser blocked a cross-origin request because the server’s response didn’t include the CORS headers allowing your site’s ori…
NotAllowedError: Failed to execute 'writeText' on 'Clipboard': Document is not focused.
The Clipboard API refused to write — the page isn’t focused, there was no user gesture, or the context isn’t secure.
Chrome DevTools: net::ERR_FAILED — a request failed with no specific reason (CORS, extension, mixed content or network)
ERR_FAILED is Chrome’s catch-all for a failed request. In DevTools it very often hides a CORS rejection, an extension, or a block…
Map another error
Popular: 4035004000xC000007BTypeErrorCritical error404NullPointerException