The function should do this:
1. A scheduled activity should open an Email (Exchange) account and retrieve new e-mails
2. The function will determine whether the sender is approved and validated against an SQL database, table (Users). If the sender is missing or not granted an email will be sent to the sender.
3. If the sender is approved, the attachments in the e-mail will be read and saved in a file area. If the attachment is PDF, JPG, or PNG, the feature will create a "screen shot" over the attachments and save the images in the SQL database, Table "Invoice." If the attechments is not PDF, JPG, or PNG an error message will be sent to the sender.
The function should be developed in .NET Core C #