Process Excel Attachments from Outlook & Send via API

## Try it out
### This n8n template monitors an Outlook mailbox for invoices, automatically parses/extracts data from them and then uploads the output to an Excel Workbook.

One of my top workflow requests, this template can save in order of 100s of hours of manual labour for you or your finance team.

### How it works
* A scheduled trigger is set to fetch recent Outlook messages to the Accounts receivable mailbox.
* Each message is analysed to determine whether or not it from a supplier and is issuing/contains an invoice.
* For each valid message, the attachments are downloaded and non-invoice documents are filtered out via AI Vision classification.
* Invoices are then processed through a AI vision model again to extract the details.
* The extracted data can then be used for reconciliation or otherwise. For this demonstration, we'll just append the row to an Excel sheet for now.

### How to use
* Ensure your Microsoft365 credential points to the correct mailbox. If a shared folder is used, toggle "shared folder" option to "on" and for the principal ID, use the email address.
* If you receive lots of other types of messages such as replies and forwards, you may want to implement additional checks to prevent processing invoices twice. The "remove duplicates" node can help with this.

### Need Help?
Join the [Discord]({{ $env.WEBHOOK_URL }} or ask in the [Forum]({{ $env.WEBHOOK_URL }}

Happy Hacking!