Stripe paid, WooCommerce pending: reconcile the order
Match the payment, its event and the order status.
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Technical errors: find your next check.
Search for your product, an error message or the problem you can see. Each guide explains how to narrow it down and what information helps with further investigation.
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Shops & payments
WooCommerce Stripe: duplicate charge after HTTP 499
Distinguish actual captures from authorisations and duplicate displays.
Google for WooCommerce: SHOPPING_PLUS blocks product sync
Check the data source, transfer and destination separately.
WooCommerce: download limit reached without receiving a file
Check a paid order’s download permission, remaining allowance and file delivery before regenerating access.
WooCommerce: blank checkout or expired session after Back
Separate an empty cart, browser history behaviour and genuine session failure with a reproducible navigation test.
WooCommerce Admin: CSS ChunkLoadError and missing assets
Use the failed file response to distinguish access blocking, missing assets and stale references behind a ChunkLoadError.
WooCommerce Stripe: Apple Pay missing after domain verification
Check the gateway, display location and eligible wallet environment before rebuilding domain registration or payment settings.
WooCommerce Stripe: Payment Method ID missing at checkout
Reconcile payments and orders first, then trace the missing reference in the specific checkout attempt.
Stripe Express Checkout: invalid-nonce 403 on cached pages
Inspect the exact Store API error and fresh-versus-aged page output without disabling security validation.
PayPal Payments in Divi checkout: payment button missing
Compare the saved checkout type with the PayPal scripts actually loaded when the payment area is unusable.
WooCommerce: manual order cannot be paid through PayPal link
Check customer assignment, order state and the payment link before changing permissions or the PayPal connection.
WooCommerce PayPal: failed refund counted in breakdown
Separate a display discrepancy from actual refunds and reconcile each attempt using its PayPal reference.
WooCommerce PayPal: one-cent mismatch after a coupon
Compare cart, creation, update and capture amounts, and evaluate the correction reported for the affected plugin version.
Mailchimp for WooCommerce: synchronisation has stopped
Trace connection, job execution and one specific order to the intended Mailchimp audience.
Websites & contact
Yoast update: Request_Helper missing and frontend fails
Check the exact error and the related plugin versions.
WordPress form sent successfully, but no email arrives
Trace one clearly marked test message.
Contact Form 7: Submit does nothing with innerText error
Investigate a missing status element and JavaScript failure when the form never starts a submission request.
Elementor will not save: HTTP 500 from admin-ajax.php
Correlate the failed save request with PHP and server logs before treating memory as the cause.
Elementor editor stuck loading after changing PHP
Find the first editor failure and compare PHP environments before assuming a general version incompatibility.
Elementor: error 413 when saving even a tiny change
Measure the complete save request and identify the rejecting server layer before changing upload or security limits.
Yoast sitemap: HTTP 500 and slow large-archive requests
Identify the failing child sitemap, request duration and server error, and separate processing failure from a blank display.
Yoast product sitemaps: duplicate URLs and missing products
Compare every child sitemap as a URL set, separating genuine omissions from variations, noindex and canonical addresses.
WP Mail SMTP: Normalizer not found in WordPress admin
Check the affected older version, error path and PHP intl availability, including the correction reported in the original case.
WP Mail SMTP Gmail: error 400 redirect_uri_mismatch
Compare the client ID and callback actually sent with the same Google OAuth client’s registered configuration.
LiteSpeed Cache: optimised images are never pulled
Trace the path from QUIC.cloud to the local image and find the missing step between optimisation, retrieval and storage.
JetFormBuilder: invalid nonce with LiteSpeed ESI as admin
Distinguish a missing form field from an expired token and compare roles with the ESI-generated output.
LiteSpeed Guest Mode: mobile menu works only after reload
Test a first-time guest separately from a repeat visitor and isolate the JavaScript or CSS optimisation involved.
LiteSpeed: PCRE error 2 with large inline CSS output
Compare large inline CSS, the parser error and generated resources; an optimisation notice alone does not prove success.
All-in-One WP Migration: corrupted .wpress archive
Check the original file, transfer integrity and import route without overwriting the last usable backup.
All-in-One WP Migration: database stuck at zero percent
Distinguish a running import from a failed background request or a PHP error in a restored theme.
All-in-One WP Migration: upload blocked despite PHP limits
Separate displayed PHP values from the effective browser, web-server and security-layer limits.
WordPress Importer: failed media import and missing images
Check the media address in the export, source availability and destination file processing as separate stages.
Gmail 550 5.7.26: replies to customers are rejected
Match the complete rejection to the actual sending path and check SPF, DKIM and DMARC according to the evidence.
Thunderbird authentication method not supported: checks
Compare server, port, TLS mode and authentication when Thunderbird rejects the selected method.
Thunderbird Linux Gmail OAuth fails after browser login
Check OAuth handoff, package type and profile separately when Google authorises access but Thunderbird cannot connect.
Thunderbird stuck on “Downloading message 1 of 140”
Identify whether authentication, one message or local storage is holding up mail retrieval.
Thunderbird 159 IMAP folders missing after an update
Check server contents, folder visibility and the documented IMAP compression regression before recreating folders.
Thunderbird export creates a large invalid or unreadable ZIP
Back up large Thunderbird profiles completely and test restoration before retiring the old computer.
Access & automation
Cloudflare Tunnel Healthy but the application is unreachable
Compare the public response, connector and origin separately.
n8n production webhook: HTTP 500 with no visible execution
Separate request arrival, execution storage and the target system.
Nextcloud upgrade stuck: needsDbUpgrade and table errors
Assess needsDbUpgrade and an already existing table safely.
UpdraftPlus Google Drive: error 401 deleted_client
Identify the OAuth client and preserve existing backups before authorising the Drive connection again.
Wordfence: wordfence-waf.php missing in extended protection
Check the bootstrap file, actual website path and PHP configuration in the correct order.
Wordfence: lost authenticator and recovery codes
Choose an authorised owner-recovery route and fully re-establish two-factor protection afterward.
n8n retry: investigate duplicate records and actions
An n8n run failed after the target already processed its request? Reconcile business references and retry behaviour before repeating the action.
n8n HTTP Request: diagnose connect ETIMEDOUT errors
n8n cannot reach an HTTPS API that opens in your browser? Separate connection establishment, source network and HTTP response.
n8n and Supabase: investigate a self-signed certificate
Postgres connection fails with a certificate-chain error? Check the endpoint, trust chain and the differences between Cloud and self-hosting.
n8n Data Table: investigate .item errors after a lookup
Item links fail after Get row(s)? Check match counts, empty results and business IDs before data is assigned to the wrong record.
n8n: excessive API calls and 429 after multiple branches
429 or concurrency errors after n8n branches converge? Inspect node invocations, item counts and the intended aggregation separately.
n8n cannot publish: entry with this name already exists
Publication reports an existing name after deployment? Compare the running n8n version with database migration history before duplicating workflows.
n8n Schedule Trigger not firing: investigate silent gaps
Scheduled processing goes quiet? Check publication, timezone and expected business output, then monitor missed successful runs.
n8n Connection lost: check the editor and running workflows
Blank n8n editor or repeated disconnects? Separate browser, connection and backend health without replaying active operations.
Instagram DMs missing in n8n despite working webhook tests
Instagram test events work but real messages are missing? Trace event delivery, the public route and the n8n production endpoint.
n8n Cloud executions stuck on Queued or Starting soon
Executions remain queued or the instance restarts? Inspect backlog, active runs and workload before replaying incoming events.
n8n SQLITE_CORRUPT: preserve the database before recovery
A corrupt SQLite database stops n8n? Preserve the original, companion files and key, then assess recovery on an isolated copy.
n8n Docker: diagnose getaddrinfo EAI_AGAIN and DNS
A hostname fails to resolve from n8n? Inspect container DNS, service names and destination ports in the relevant network.
Nextcloud file locked: check DAV locks and write access
Saving fails with Sabre DAV Locked? Identify the lock mechanism and distinguish it from filesystem permissions before removing anything.
Nextcloud updater: Write permissions check still fails
An update stops at its write-permission check? Identify the exact path, effective PHP user and mount permissions before changing ownership.
Nextcloud ignores php.ini: check effective PHP settings
Upload limits or PHP values remain unchanged? Compare web SAPI, CLI and the configuration actually loaded before reinstalling PHP.
Nextcloud Collabora: diagnose Document loading failed
Office connection appears healthy but documents will not load? Check browser access and both server-to-server connection directions.
Nextcloud group folders missing after update: check IDs
Team files remain on storage but folders disappear from Nextcloud? Check app state, folder configuration and group access before recreating them.
Nextcloud update: investigate unknown files detected
Unknown files detected within the installation folder? Identify the reported files and preserve evidence before cleaning the installation.
Nextcloud deletes client files after a storage change
Files disappear after a mount or sharing change? Pause synchronisation, preserve local copies and establish server and storage state.
Nextcloud reads Samba files but cannot save changes
Reading works but saving returns Permission denied? Distinguish a local bind mount from SMB access and identify the effective writing identity.
Nextcloud AIO domain validation fails behind a reverse proxy
AIO reports a domain or reverse-proxy problem? Check DNS, APACHE_PORT and the upstream actually reachable from the proxy.
Make Custom Webhook: check Unauthorized and API-key access
Opening a webhook URL returns Unauthorized? Check its API-key header, IP rules and actual hook identity without removing protection.
Make Google Sheets / Drive: No access token specified
A Google connection exists but Sheets or Drive return 403? Separate OAuth completion, connection identity and access to the actual file.
Make: linked feeder was not found when resuming a run
An incomplete Make execution fails at an aggregator? Inspect saved run state, Source Module and data completeness before restarting.
Make Google Sheets Search Rows returns just one bundle
Several spreadsheet rows but one result? Compare spreadsheet ID, sheet, range and the actual module output before downstream filters.
Make HTTP: Airtable webhook returns 422 but curl works
curl works but Make returns a parameter-validation error? Compare the transmitted JSON body, headers and resolved values.
Make Iterator: Array empty despite existing source data
The source contains several items but Iterator receives nothing? Check the field path, array type and module reference in the same execution.
ERPNext blocks backdated batch entries after reconciliation
A later Stock Reconciliation blocks an earlier batch entry? Inspect document chronology, affected batch and version before changing records.
Frappe / ERPNext Germany: conflicting Tenacity dependencies
Installation requires incompatible Tenacity 8.2 and 9.1 ranges? Compare exact app revisions and dependencies instead of forcing alternating versions.
Frappe CRM asset build: DataImport MISSING_EXPORT
CRM assets fail with MISSING_EXPORT after a Frappe update? Compare the component interface and matching CRM version before applying local patches.
SWAG DuckDNS KO: diagnose wildcard certificate renewal
Check the DuckDNS response, domain ownership and published TXT record when SWAG cannot renew its wildcard certificate.
Certbot DNS SERVFAIL: inspect domain and CNAME resolution
Trace A, AAAA and CNAME answers to the authoritative servers when Certbot fails with DNS SERVFAIL.
Let's Encrypt AAAA error: check the IPv6 validation path
Compare IPv4 and IPv6 on the same challenge path when the website works but certificate renewal fails.
Certbot renewal fails: check manual auth hooks and timers
Check the actual Certbot executable, authentication method and scheduler separately before a certificate expires unnoticed.
Certbot wildcard with --standalone: DNS-01 is required
Identify the unsupported authenticator combination and plan a renewable DNS challenge for your wildcard certificate.
nginx on Windows: diagnose cannot load certificate errors
Compare nginx’s certificate path with the actual file, startup directory and permissions before issuing replacement certificates.
Let's Encrypt HTTP-01: timeouts from some validation paths
Compare the same challenge path from independent networks and match both successful and missing requests to your logs.
Synology DSM: maximum certificate requests reached
Separate the DSM message from a confirmed ACME rate limit and check domain validation and certificate assignment.
Cloudflare WARP private DNS: diagnose missing replies
Separate resolver reachability, DNS policy and UDP/TCP behaviour when WARP can no longer resolve internal names.
cloudflared QUIC CRYPTO_ERROR 0x178: check the handshake
Distinguish UDP reachability from a successful QUIC handshake and run a limited HTTP/2 comparison where appropriate.
cloudflared on Linux: .local origin returns no such host
Check name resolution inside the connector environment when a .local service works on other devices.
Cloudflare Tunnel ERR_TOO_MANY_REDIRECTS: trace the loop
Trace Location headers and the origin scheme when an application enters a redirect loop through the tunnel.
cloudflared connectTimeout: immediate origin i/o timeout
Compare saved remote configuration, expected units and elapsed time when an origin request times out immediately.
Cloudflare Tunnel WebSocket 1006: inspect the handshake
Trace the WebSocket handshake to the origin when live updates fail but ordinary HTTP requests still work.
Invoices & PDF
PEPPOL-EN16931-R041: missing invoice allowance base amount
Locate the affected allowance or charge in the XML.
Stirling PDF cannot save Thai, Cyrillic or Chinese form text
Distinguish generation failure from a display issue.
Stirling PDF visible signature fails on non-ASCII names
Separate visible-signature font errors from token access and cryptographic signature validation.
Stirling PDF crops the wrong area: verify the exported pages
Compare the crop preview with saved output on clearly identifiable pages when the selected area shifts.
Stirling PDF deleted text reappears in download or print
Check the saved PDF for old text and distinguish editing, covering and permanent removal.
Stirling PDF slow zoom and scrolling with vector documents
Measure opening, navigation and server processing separately when technical drawings become difficult to use in the viewer.
Stirling PDF Entra ID login: missing preferred_username
Compare ID-token claims, UserInfo and supported user mapping when Entra sign-in fails in Stirling PDF.
Mustang validation report breaks on & in the filename
Separate a broken validation report from an invalid invoice and compare identical contents under a neutral filename.
Mustang wasCompletelyValid true despite invalid PDF/A
Read PDF/A, invoice XML and overall results separately when wasCompletelyValid returns true despite a PDF failure.
XRechnung 3.0.2 validators disagree: compare rule bundles
Compare complete rule bundles, scenarios and versions when the same XRechnung passes one check and fails another.
Mustang invoice import NumberFormatException in decimal data
Locate the exact numeric field and separate XML formatting errors from overly strict importer handling.
Mustang UBL import: allowances missing from invoice totals
Reconcile line totals, document allowances, charges and the payable amount separately when import reports an arithmetic difference.
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