Users with appropriate permissions are able to view Dashboards offline.
After a Sandbox refresh and while viewing MyInsights Dashboards online outside of a MyInsights Lightning Component, the report will not display and the page will show 404 - Not Found error.
When viewing a Lightning MyInsights report, the report will not display and instead "AccessDeniedAccess Denied" will appear in its place.
After a Sandbox refresh, the associated HTML Report record must be published again for online use.
To publish a HTML report visualization:
- Select the Publish button on the relevant HTML Report record page.
- Refresh the page.
- Check the updated values of the Status_vod, Published_Date_vod, and Status_Details_vod fields.
CRM Help Documentation: Configuring MyInsights for Admins & End-users