At a glance
The three things almost every setup question comes back to.
SET UP ONCE
Connector Setup + the three linking tables (VAT, UOM, Payment Method) — do this before posting your first live invoice.
CHECK STATUS HERE
Every submission shows as Submitted or Failed on the E-Invoice Header. The E-Invoice Log has the full request/response.
MOST FAILURES ARE MAPPING GAPS
A missing row in a linking table, or a 0% combination in VAT Posting Setup, causes more issues than the API connection itself.
Initial setup
Complete these steps once per company, before posting invoices you intend to submit as e‑invoices.
Open Connector Setup
Search for Connector Setup in Business Central. Enter your Peppol ID (format 0235:<your identifier>) and your default Commodity Code (G for goods, S for services, B for both).
Set HS / SAC codes
If your Commodity Code is G, set the default HS Code. If it's S or B, set the default Service Accounting Code (SAC). These are used when a line-level override isn't present.
Populate VAT Linking
For every VAT Prod. Posting Group you invoice under, add a row mapping it to the corresponding e-invoicing VAT Category and percentage. See VAT mapping below for how this is used.
Populate UOM Linking
Map each Base Unit of Measure used on your items to the standard e-invoicing UOM code. Any unmapped unit falls back to H87 (piece).
Populate Payment Method Linking
Map each Business Central Payment Method Code to the e-invoicing Payment Means Code. Unmapped methods fall back to code 10 (cash/other).
Post a test invoice
Post a test invoice in your sandbox environment and confirm it reaches Submitted status before going live with real customer invoices.
Configuration reference
VAT Linking
Each row maps a VAT Prod. Posting Group to a Connector VAT Category and percentage used in the e-invoice line. If a product posting group used on an invoice line has no matching row here, the line is submitted without VAT category/percentage data — this is one of the most common causes of an unexpected VAT amount. See Troubleshooting: VAT shows as 0.00.
UOM Linking
Maps an item's Base Unit of Measure to the UN/CEFACT unit code expected by the e-invoicing standard (e.g., PCE, KGM, LTR). Items without a mapped unit default to H87.
Payment Method Linking
Maps your Business Central Payment Method Code (set on the customer) to the e-invoicing payment_means_code. Bank account details are only required and included when the mapped code is 30 (credit transfer).
Commodity / HS / SAC codes
Set at the company level in Connector Setup. G (goods) requires an HS Code; S or B (services / both) requires a Service Accounting Code. If your business sells both goods and services with different codes per item, request a line-level override field from your implementation partner rather than relying on the single company-wide default.
Daily use
Once configured, the connector works alongside your normal posting process:
Post a Sales Invoice
Post a Sales Invoice as usual — no change to your existing workflow.
Submit e Invoice
The connector prepares the e invoice JSON from the posted invoice, and the user submits it manually using the “Submit e Invoice” action. After submission, the user can manually refresh the status using the “Refresh” action to retrieve the FTA reference and updated delivery status.
Check Status
Check the E-Invoice Header list for the resulting status: Submitted or Failed.
Review E-Invoice Log
For any invoice, open the related E-Invoice Log entries to see the exact request sent and response received — useful for your own audit trail as well as troubleshooting.
Troubleshooting
COMMON
VAT Prod. Posting Group is set (e.g. "VAT5") but Total VAT (AED) shows 0.00
WHY THIS HAPPENS
The e-invoice VAT amount is not derived from the code's name — a group named "VAT5" carries no numeric meaning by itself. Business Central calculates VAT using the row in VAT Posting Setup matching the line's combination of VAT Business Posting Group + VAT Product Posting Group. If that specific combination has a 0% rate, or if the VAT Business Posting Group is blank when you expected it to be populated (e.g., from the customer), the line will correctly calculate to 0.00 even though the product posting group name suggests 5%.
HOW TO FIX
- Open VAT Posting Setup and find the row for your actual VAT Business Posting Group + VAT Product Posting Group combination.
- Confirm the VAT % field on that row is set correctly (not 0).
- Check why the VAT Business Posting Group is blank, if unexpected — this usually traces back to the customer card or G/L account setup.
- Because the invoice is already posted, use Correct → Cancel and create corrective credit memo (or your standard correction process) after fixing the setup, then re-post.
COMMON
Submission status shows Failed
WHY THIS HAPPENS
Usually a validation error returned by the e-invoicing endpoint — most often a missing linking table entry, an invalid Peppol ID format, or a required field (like HS Code or SAC) left blank for the commodity type in use.
HOW TO FIX
Open the E-Invoice Log entry of type Error for that invoice and read the captured error message — it identifies the specific field or validation rule that failed. Cross-check against the Configuration reference above, correct the mapping, then resubmit.
OCCASIONAL
Line quietly falls back to a default UOM or payment code you didn't expect
WHY THIS HAPPENS
This is by design, not a bug: unmapped units of measure fall back to H87, and unmapped payment methods fall back to 10, so submission isn't blocked by a missing mapping. But it means the submitted e-invoice may not reflect the correct unit or payment method.
HOW TO FIX
Add the missing row to UOM Linking or Payment Method Linking for the specific code involved. Previously submitted invoices are not automatically resubmitted — only new postings will use the corrected mapping.
OCCASIONAL
Currency exchange rate missing or looks wrong on a non-AED invoice
WHY THIS HAPPENS
The connector pulls the exchange rate for the invoice's currency as of the Posting Date from Business Central's standard Currency Exchange Rate table. If no rate exists for that date, the lookup will fail.
HOW TO FIX
Confirm an exchange rate exists for the relevant currency covering the invoice's posting date in Currency Exchange Rates, then resubmit.
Frequently Asked Questions