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Store documents and information to a secure Microsoft SharePoint website. Configure the frevvo SharePoint Connector for your tenant then use the SharePoint wizard to connect your forms/flows to the SharePoint website for document storage. . Refer to the SharePoint Connector topic for the details. 

Connector Security

 connectors installed on-premise should only be accessible to the frevvo server i.e. http://localhost:8983/, and  server and should not be remotely accessible. Most customers don’t allow external http   recommends only allowing HTTPS access to a the server (only httpsnot external HTTP access). Since the connector(s) is not exposed over httpsHTTPS, remote code execution vulnerability can be mitigated (a remote attacker cannot exploit this vulnerability as it is not exposed). Another option to enhance connector security is to block  

If you choose to allow external access to

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HTTP, you should only allow requests with paths starting with /frevvo for port 8082 (or the port you are using for frevvo and the Connector(s)). 

See also Database Connector Security.