| License Key | string | | Input the license key you received from us. |
| Production API Client ID | string | | Production API client identifier. |
| Production API Client Secret | string | | Production API client secret. |
| Production Organisation ID | string | | To get the production credentials, follow the instructions in the “Pingen Account Configuration” chapter. |
| Staging API Client ID | string | | Staging API client identifier. |
| Staging API Client Secret | string | | Staging API client secret. |
| Staging Organisation ID | string | | To get the staging credentials, follow the instructions in the “Pingen Account Configuration” chapter. |
| Environment | radio | Staging | Recommended to try Staging first (no letters sent, no costs). Switch to Production once verified. |
| Default Sending Speed | radio | Economy | Priority mail is faster and more expensive than Economy. |
| Default Sending Color | radio | Grayscale | Black and white prints are cheaper; color prints look nicer. |
| Default Printing Mode | radio | Simplex | Indicates if printing should be Simplex or Duplex. |
| Default Address Position | radio | Left | Indicates if the recipient address is on the left or right side of the PDF invoice. |
| Sending mode | radio | Manual | Modes: Manual (explicit send), Clients (only if enabled), Automatic (always send unless disabled). |
| Enable Client Area | checkbox | no | Allows clients to enable/disable sending invoices with Pingen from the Client Area. Requires Sending Mode set to Clients or Automatic. |
| Trigger | radio | OnOrderAccept | Choose whether to send on invoice creation or when the order is accepted. Invoices without orders (e.g., renewals) are sent on creation. |
| Payment Gateways Restriction | string | | Comma-separated list of WHMCS payment gateway module names (e.g., paypal,checkout). Empty = applies to all gateways. |
| Invoice Product Addon ID | numeric | | Only send if invoice contains the addon with the configured ID. Empty = no restriction. |
| Add fee on invoice creation | checkbox | no | Apply the price of the configured addon as a fee on each new invoice. Product addon must be hidden and one-time priced. Recommended with Send Mode = Clients and Client Area enabled. |
| Send when zero | checkbox | no | Also send when invoice balance is <= 0. |
| First overdue | checkbox | no | Also send when first overdue notice is due. |
| Second overdue | checkbox | no | Also send when second overdue notice is due. |
| Third overdue | checkbox | no | Also send when third overdue notice is due. |
| Late fee | checkbox | yes | Resend when late fee is added to invoice. |
| Abort e-mails | checkbox | yes | Don’t send e-mails to clients when invoice is sent via Pingen. |
| Notify admins | checkbox | yes | Notify WHMCS administrators when an invoice has been automatically sent via Pingen. |
| Absolute storage path | string | | Must be an absolute path to a writable directory not accessible from the web. Used as temporary storage while sending files. |
| Access control | checkboxes | | Ensure addon access is granted to appropriate staff groups. |