Dynamics 365 is accessed via the OData v4 REST API, which requires a single XML file containing all metadata for an instance to be retrieved prior to any other actions. Dynamics 365 incorporates a lot of objects which makes this has many objects making the metadata file quite large in most cases, so S4D caches a copy locally to improve performance.
Because of this caching mechanism, S4D will not recognize schema changes in your Dynamics 365 instance immediately, and it will may be necessary to remove manually refresh the cached copy.
TODO: The Status page metadata removal/reload offers an immediate means of refreshing cached metadata files, and S4D offers a scheduled task to do this at regular intervals.
Metadata files are automatically downloaded and cached in the directory defined in the \App_Config\Modules\S4D\S4D.config file:
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Files are named based on the Dynamics 365 domain. It is generally safe to delete any files file not in use, a . A fresh copy will be automatically downloaded when it is next required.
If the web server webserver process does not have write access to this location then the metadata file will need to be download downloaded for every Dynamics API request , which may have a an impact on performance impact.