The add-in should work in Outlook cloud version or desktop version. Once installed, on the first use, it should ask for the entity code and password. This information must be recorded in order not to be requested in each use.
When we open an incoming mail, the add-in button should be available to save the mail. The user must also have to select the document type. When saving, the plugin will create a record in the table "messages" with the message and n more records in the table "attachments".
The database must be made in Microsoft SQL Sever and the plugin should not communicate directly with the database. It must communicate through an API to be developed in asp.net core.
The "users" table will be populated externally. The API will use this table only for querying and validating access credentials. The "Types" table will also be query-only.