Error map
HTTP error (media upload) WordPress Media: “HTTP error.” when uploading images
WordPress · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (12). 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 (12)
Upload error: File too large (LIMIT_FILE_SIZE / file exceeds maximum upload size)
The uploaded file is larger than the limit set by the API, framework or server.
Cloudflare 413 Request Entity Too Large (upload over the plan limit)
The request body is larger than Cloudflare allows through the proxy — 100 MB on Free/Pro, 200 MB Business, 500 MB Enterprise defa…
WordPress: Sorry, you are not allowed to upload this file type / Sorry, this file type is not permitted for security reasons
WordPress blocked the upload because the file extension/MIME type isn’t in its allowed list (SVG, JSON, WEBP on old versions, fon…
Upload error: File type not allowed / unsupported file type
The upload was rejected because the file’s type — extension, MIME type or actual content — isn’t on the allowed list.
HTTP 100 Continue
An interim response telling the client to go ahead and send the request body — normal when the client sent Expect: 100-continue.
Upload error: checksum mismatch (BadDigest / Content-MD5 did not match / XAmzContentSHA256Mismatch)
The server computed a different checksum for the data it received than the one your client declared, so it rejected the upload as…
HTTP 417 Expectation Failed
The server or a proxy can’t meet the Expect header in the request — almost always Expect: 100-continue.
WordPress: The link you followed has expired
Usually an upload (theme, plugin, media) larger than PHP’s upload/post limits — WordPress receives an empty request and shows thi…
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.
S3 EntityTooLarge: Your proposed upload exceeds the maximum allowed size
A single PUT can be at most 5 GB (and presigned POST policies can set lower limits); larger files must use multipart upload.
WordPress: Unable to create directory wp-content/uploads/2026/10. Is its parent directory writable by the server?
PHP can’t write to wp-content/uploads — wrong ownership/permissions, a wrong upload path, full disk, or open_basedir restrictions.
WordPress: The uploaded file could not be moved to wp-content/uploads/2026/10
PHP received the upload but couldn’t move it from the temp directory into uploads — permissions, disk space, or open_basedir/temp…
Two steps away (33)
HTTP 413 Content Too Large (Request Entity Too Large)
The request body is bigger than the server is willing to accept — usually a file upload over the configured limit.
PHP upload error 1: The uploaded file exceeds the upload_max_filesize directive in php.ini
The uploaded file is bigger than PHP’s upload_max_filesize, so PHP discarded it.
API Error: Too many concurrent requests (concurrency limit reached)
You have more requests in flight at once than the API allows for your key — even if your requests-per-minute rate is fine.
Too many open files (EMFILE)
The process hit its file-descriptor limit — sockets, files and pipes all count.
Lambda: Request must be smaller than 6291456 bytes for the InvokeFunction operation (RequestEntityTooLargeException)
The event payload (or response) is over Lambda’s 6 MB synchronous limit (256 KB for async invocations).
Lambda: Unzipped size must be smaller than 262144000 bytes
The function code plus layers exceed Lambda’s 250 MB unzipped limit for zip deployments.
WordPress: 403 Forbidden on wp-admin, wp-login.php or admin-ajax.php
The server or a security layer refused access to WordPress admin URLs — file permissions, a security plugin/WAF rule, ModSecurity…
WordPress: Are you sure you want to do this? Please try again. (nonce check failed)
A WordPress security nonce didn’t validate — the page was open too long, cached, or a plugin/theme form is broken.
WordPress: Post-processing of the image failed likely because the server is busy or does not have enough resources
The image uploaded but WordPress couldn’t generate its resized versions — memory/CPU limits or Imagick problems.
HTTP 415 Unsupported Media Type
The server refuses the request because the body’s Content-Type isn’t one it accepts.
WordPress: Sorry, you are not allowed to access this page.
Your user role lacks the capability for that admin screen — or the database table prefix / user capabilities are out of sync afte…
API Error: Invalid type — expected integer, received string
A request field has the wrong data type — a string where the API expects a number, a number where it expects a boolean, an object…
Warning: Cannot modify header information - headers already sent
You called `header()`, `setcookie()` or `session_start()` after output had already been sent to the browser.
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…
HTTP 411 Length Required
The server refuses a request with a body but no Content-Length header.
npm ERR! code EINTEGRITY — sha512 integrity checksum failed
A downloaded package’s hash doesn’t match the integrity value in package-lock.json — a corrupted cache, a changed tarball, or a l…
API Error: Job / operation not found or expired (async task ID unknown)
The status URL or job ID for an asynchronous operation (export, import, render, batch) doesn’t exist any more, or never existed.
Console: Failed to find a valid digest in the 'integrity' attribute for resource … with computed SHA-256 integrity
A `` or `` with an `integrity` hash was blocked because the downloaded file does not match that hash.
HTTP 400 Bad Request
The server could not understand the request because its syntax, headers or body are malformed or invalid.
HTTP 407 Proxy Authentication Required
A proxy between you and the server requires credentials before it will forward your request.
HTTP 428 Precondition Required
The server requires a conditional request (If-Match / If-Unmodified-Since) to prevent lost updates, and you didn’t send one.
PHP Fatal error: Maximum execution time of 30 seconds exceeded
The script ran longer than `max_execution_time` and PHP stopped it.
WordPress: There Has Been a Critical Error on This Website
A PHP fatal error (usually from a plugin or theme) stopped WordPress; the real error is in the debug log or recovery-mode email.
Warning: Unknown: Input variables exceeded 1000. To increase the limit change max_input_vars in php.ini.
The form submitted more fields than PHP’s max_input_vars allows; extra fields were silently dropped.
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.
AWS S3: AccessDenied (403) when calling GetObject / PutObject
An IAM policy, bucket policy, ACL/ownership setting, Block Public Access or KMS key policy denied the S3 request.
AWS S3: NoSuchKey / NoSuchBucket — The specified key/bucket does not exist
S3 found no object at that key (or no bucket with that name in the region/account you’re calling).
BucketAlreadyExists: The requested bucket name is not available
S3 bucket names are global across all AWS accounts, and someone else already uses this one.
Linux: Permission denied
Your user (or the service user) lacks read/write/execute permission on a file, directory or one of its parents.
WordPress: Installation failed: Could not create directory (plugin/theme install or update)
WordPress can’t write to wp-content/plugins, themes or upgrade — ownership/permissions or disk space.
To perform the requested action, WordPress needs to access your web server. Please enter your FTP credentials to proceed
WordPress can’t write directly to its files (ownership differs from the PHP user), so it falls back to asking for FTP details.
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