How does ml-connector handle Sage 50's Windows SDK requirement?

ml-connector runs on a Windows machine where Sage 50 is installed and has access to the company data files. It authenticates using the same SDK credentials you provide (ApplicationID and CompanyPath for US, DataPath for UK) and queries GL and payment records by modified date. Sage 50 SDK requires exclusive access, so the integration user must not be logged in interactively while the sync runs.

What happens to PayPal refunds in Sage 50?

Refunds are posted as separate journal entries into the same GL account mapped to PayPal deposits. Each refund is tagged with the original PayPal transaction ID so you can trace it back to the payment it reverses. The GL account balance at any point reflects all deposits and refunds in chronological order.

Does ml-connector handle PayPal's 31-day transaction search limit?

Yes. ml-connector polls PayPal on your configured schedule and caches the last sync timestamp to avoid re-importing old transactions. If you set the poll interval to weekly or less, you will not exceed the 31-day window. For initial backfill of older transactions, you can request a longer custom window or backfill them manually into Sage 50 once, then let the integration manage ongoing syncs.

Sage 50PayPal

Sage 50 and PayPal integration

Sage 50 runs your accounting and GL. PayPal processes your payments. Connecting the two keeps your payment records in sync with your general ledger without manual re-keying. Payments and refunds from PayPal flow into Sage 50 as journal entries and vendor payment records on a schedule you control. ml-connector handles the very different interfaces on each side - the Windows SDK on Sage 50 and the REST API on PayPal - and moves the data securely with a full audit trail.

How Sage 50 works

Sage 50 Accounting (US and UK editions) is a Windows desktop application that exposes vendors, purchase invoices, payments, GL accounts, general journal entries, and bank records through a local .NET SDK or COM/ODBC layer. There is no cloud REST API; integration requires a Windows process with direct access to the company data files on the same machine or LAN. Authentication uses Windows-local username and password plus an ApplicationID (US) or DataPath (UK). Sage 50 has no webhooks or event stream, so payment records are read by polling the GL journal or querying records modified since the last sync.

How PayPal works

PayPal REST API exposes orders, payments, captures, refunds, invoices, transactions, and subscriptions through JSON REST endpoints. Authentication uses OAuth 2.0 Client Credentials flow with Bearer token caching. PayPal can push payments and refund events via HTTPS webhooks with RSA-SHA256 signature verification required on every call. Transaction search is available but limited to a 31-day window, and each transaction list returns a maximum of 500 results. PayPal has no native GL account objects and no vendor registry.

What moves between them

Payment records move from PayPal into Sage 50. PayPal webhooks and scheduled queries return payments, refunds, and payouts. ml-connector maps each PayPal transaction to a Sage 50 GL account and optionally to a vendor record if the payment is linked to an invoice. Refunds flow the same direction. Payment data populates Sage 50 general journal entries and vendor payment records on the cadence you configure. Sage 50 payment records are not written back to PayPal, so the integration is unidirectional.

How ml-connector handles it

ml-connector stores Sage 50 SDK credentials (ApplicationID or DataPath, username, password) and PayPal OAuth2 credentials encrypted at rest. On the Sage 50 side, it opens a Windows SDK session and queries the GL journal and payment records by modified date or transaction date. On the PayPal side, it maintains a cached Bearer token and refreshes it when calls return 401, and it accepts incoming webhook POST requests, verifies the RSA-SHA256 signature using the webhook ID and cert from PayPal, and processes the events. Because Sage 50 SDK requires exclusive access and has no webhook callback, ml-connector polls on your schedule rather than waiting for a Sage 50 push. PayPal transactions are matched to Sage 50 GL accounts by a mapping you configure (e.g., PayPal receives -> Undeposited Funds account). Refunds are posted as contra entries into the same GL account. Every transaction carries a full audit trail, so reconciliation mismatches can be traced back to the source.

A real-world example

A mid-sized e-commerce retailer runs Sage 50 Accounting for AR and GL, and accepts customer payments through PayPal. Before the integration, the bookkeeper exported PayPal transactions weekly and manually keyed them into Sage 50 as journal entries and vendor payments, a process that took hours and created frequent data-entry errors. Reconciliation between the GL and PayPal records happened only at month-end close and often revealed discrepancies that required manual rework. With Sage 50 and PayPal connected, each PayPal payment posts into the Undeposited Funds GL account automatically as the transaction clears, and monthly bank deposits flow through the GL without re-keying. Reconciliation is now a daily check that takes minutes rather than a month-end surprise.

What you can do

Post PayPal payments and refunds into Sage 50's general ledger as journal entries on a schedule you control.
Map PayPal transactions to Sage 50 GL accounts and vendor records so payments land on the correct accounts.
Authenticate Sage 50 via Windows SDK with ApplicationID or DataPath, and PayPal via OAuth2 bearer token with webhook signature verification.
Handle PayPal webhook events with RSA-SHA256 signature verification and process scheduled transaction queries from the 31-day PayPal transaction search window.
Provide a full audit trail on every payment record so reconciliation discrepancies can be traced back to the source.

Questions

How does ml-connector handle Sage 50's Windows SDK requirement?: ml-connector runs on a Windows machine where Sage 50 is installed and has access to the company data files. It authenticates using the same SDK credentials you provide (ApplicationID and CompanyPath for US, DataPath for UK) and queries GL and payment records by modified date. Sage 50 SDK requires exclusive access, so the integration user must not be logged in interactively while the sync runs.
What happens to PayPal refunds in Sage 50?: Refunds are posted as separate journal entries into the same GL account mapped to PayPal deposits. Each refund is tagged with the original PayPal transaction ID so you can trace it back to the payment it reverses. The GL account balance at any point reflects all deposits and refunds in chronological order.
Does ml-connector handle PayPal's 31-day transaction search limit?: Yes. ml-connector polls PayPal on your configured schedule and caches the last sync timestamp to avoid re-importing old transactions. If you set the poll interval to weekly or less, you will not exceed the 31-day window. For initial backfill of older transactions, you can request a longer custom window or backfill them manually into Sage 50 once, then let the integration manage ongoing syncs.

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