Correct the resource references and secure delivery path. A migration can leave old URLs in CSS, content and generated assets.
Capture the blocked request context
Open the HTTPS page with Console and Network visible. Record the insecure resource URL, the element or stylesheet that requested it, and the browser’s message. Distinguish mixed-content handling from a missing file or certificate failure. An image that appears in one browser does not prove that all insecure requests are acceptable, especially for scripts or styles.
Find where the old URL is stored
Trace the request to post content, theme settings, custom CSS or generated assets. Check background images and font declarations as well as visible image tags. Use the application’s supported migration tooling for stored data. WordPress values may be serialized, so a blind text replacement in a database dump can damage unrelated configuration.
Confirm the HTTPS destination works
Request the intended secure asset and verify its certificate, status and content. Simply replacing the scheme is insufficient if the destination does not serve the file correctly. For third-party resources, use the vendor’s supported secure address or remove the dependency when no suitable delivery exists. Do not weaken browser security to conceal the failure.
Regenerate derived assets deliberately
After correcting the source, rebuild generated CSS or optimization output through the responsible tool. Invalidate affected cached HTML and assets where required. Compare a fresh browser session with an existing one, and inspect the actual requests. If the problem returns after regeneration, a stored source or configuration still contains the old reference.
Review a template sample before closing
Check the homepage, article, product, account and contact templates, including mobile menus and lazy-loaded media. Confirm forms and essential scripts work over HTTPS without policy errors. Keep the migration backup and previous configuration until these checks pass. Save the corrected source locations so a later import or theme update does not reintroduce insecure URLs.
Symptom-to-cause worksheet
| What you observe | What to investigate | Next check |
|---|---|---|
| Only background image fails | Old URL in stylesheet or generated CSS | Trace request initiator |
| Secure URL also fails directly | Asset or certificate problem | Fix HTTPS delivery before replacing references |
| Old URL returns after regeneration | Owning source still unchanged | Inspect theme or builder settings |
Worked investigation scenario
This is an illustrative case, not a measured Velonic result. Suppose post images use HTTPS after migration, but a generated stylesheet still points a background to HTTP. Trace the request initiator to its stored builder setting, correct that source with supported tooling and regenerate output. Check another page using the same setting. If the reference returns after rebuilding, do not declare the cache purge successful: an uncorrected source is recreating the insecure URL.
Put it into practice
- Separate mixed content from missing-resource errors.
- Use serialization-aware migration tooling.
- Retest generated assets and lazy-loaded components.
AI-assisted educational content prepared for the Velonic resource library. How these guides are prepared.