After migrating an Oxygen site or changing the domain in your hosting, you must follow these steps in order:
- Run a search and replace on the database to update the old domain to the new domain (the Better Search Replace plugin is good for this). This isn't needed if you have used a migration plugin that runs a search and replace for you, such as All In One Migration
- Save your permalinks twice via Settings > Permalinks
- Resign your shortcodes via Oxygen > Settings > Security
- Regenerate your CSS cache via Oxygen > Settings > CSS Cache
- Re-save your licence key via Oxygen > Settings > License so that your site can use one-click updates when a new version is available
You may also need to open each template in the admin area and click the Update button on the right-hand side but I've only found that to be required on a handful of sites.
If you have any caching plugins installed you will also need to clear the caches.