Introduction

Migrating decades of AS400 (IBM iSeries) or JD Edwards (JDE) data into a modern Microsoft Dynamics 365 Finance & Operations (D365 F&O) environment may feel daunting.

You might’ve been running ol’ reliable out of a clean room—or a closet—for decades, without fail. Now, it’s time for a change. An upgrade in many ways; a change, unquestionably.

More experienced users may be ready to stage a revolt, but your new hires take one look at the green screen and ask if you’re joking.

You know, however, that behind that virtual terminal sits a trove of Physical and Logical DB2 Files just waiting for someone to WRKQRY their way through 30 years of transactions. Those days are coming to an end, though, because how many of us know what WRKQRY is anymore—let alone that F14 shows additional columns (or that there IS an F14 BUTTON)?! 🤯

But, alas, the time has come. We’re joining the 21st century.

How do we get the data from AS400 to Dynamics 365 Finance?

Below, we’ll explore a roadmap to help you accomplish a smooth transition without sacrificing data accuracy, security, or sanity.

1. Why Migrate Legacy Data into D365 Finance & Operations?

Modern ERP Advantages

D365 F&O offers advanced analytics, integrated workflow automation, and more agility than legacy systems. By centralizing your financial, supply chain, and operational data, you gain a unified, real-time view of business performance.

This streamlined ERP system enables better decision-making, greater scalability, and improved customer experience. For companies dealing with complex supply chains, automating business processes helps reduce manual errors and increases operational efficiency.

This is why many companies migrating from JD Edwards, Oracle, NetSuite, and SAP are turning to Microsoft Dynamics. The ability to consolidate operations and provide better business insights is key to meeting modern business needs.

Regulatory Compliance

Maintaining historical financial data in a cloud-based platform ensures readiness for audits and meets legal retention requirements. No more rummaging through multiple file systems or outdated databases.

Business Intelligence Gains

Consolidating data from disparate systems unlocks better insights and more accurate forecasting—vital for making data-driven decisions that can steer your organization’s future. The enhanced functionality of D365 F&O allows for more accurate financial management and improved visibility across your sales process and supply chain.

2. Scope & Plan: The Importance of a Thorough Data Audit

Identify Critical Records

Pin down the essential transaction histories, customer/vendor details, and financial ledgers that must be available in your D365 F&O environment. Plan ahead for compliance: understand retention laws (SOX, HIPAA, etc.) so you don’t accidentally archive away data you need.

Cleanse & Validate

Spot duplicates, missing fields, and obsolete codes in your AS400 or JD Edwards EnterpriseOne and JD Edwards World databases. Establish standard naming conventions and data formats to prevent headaches once everything’s in D365 F&O.

Cleaning up data is critical, especially when handling complex modules like payable, receivable, procurement, and sales orders. Mapping these entities accurately reduces the risk of misalignment in business operations post-migration.

Engage Stakeholders

Bring in finance, operations, IT, and other business units early. Get clarity on which datasets are indispensable for daily operations, month-end closings, or advanced analytics. Ideally, a Steering Committee exists for the project—identify how to work with the steering committee to raise data migration challenges.

3. Storing & Version-Controlling Your Data Migration Scripts

Use Azure DevOps or Git

Keep all ETL (Extract, Transform, Load), integration, and Data Management Framework (DMF) scripts in a centralized, version-controlled repository—preferably the same one your project team already uses. This single source of truth lets you audit changes, roll back to earlier versions, and collaborate more effectively.

Pristine Data Extraction

Always maintain a master copy of the raw data extracted from AS400 or JD Edwards. This pristine dataset remains untouched by cleanup or transformation steps. Then, copy this master data to a staging environment where you apply mapping rules, data-cleansing scripts, or any required modifications.

4. Creating a Solid Migration Checklist: Checkpoints & Automation

Entity Inventory

List every data entity (e.g., customers, vendors, chart of accounts, orders, sales orders, ledger entries). Note dependencies: global address book goes in early, vendors must load before purchase orders, customers before sales orders, and so on.

Push-Button Execution

Use platforms like Azure Data Factory, SSIS, or the D365 DMF to automate recurring steps. Modularize your scripts so you can run individual segments (such as vendor data) or the entire plan without unnecessary complexity.

Validation Steps

Check record counts, confirm transformations, and track errors using logs. Maintain a consistent naming convention for file outputs, entities, and logs, ensuring any issues can be traced back quickly.

5. Handling Delta Loads for Ongoing AS400 or JD Edwards Activity

Why Delta Loads Matter

If your legacy systems continue processing transactions while you prepare for go-live, incremental (delta) loads are essential. They let you sync any new or updated records to D365 F&O until final cutover.

Scheduling & Tracking

Decide if you’ll run delta loads daily, weekly, or in real-time. Whichever cadence you choose, keep a comprehensive record of which data has been migrated so you don’t re-import duplicates or miss new transactions.

6. Designing Data Migration with Reporting in Mind

Data Model Alignment

Align D365 F&O entities with the dimensions and measures critical to your reporting. If certain legacy codes are essential for building trend analyses, keep them alive in the new system.

Continuous Testing

Build early prototypes of Power Apps, Power BI, or SSRS reports against partial data sets. Validate key metrics to confirm the final reports match historical baselines.

7. Staging Environment & Transformations: Validate, Clean, Repeat

Isolation & Error Handling

Conduct transformations—field mapping, code standardization, data cleansing—in a secure staging area. This sandbox approach lets you spot and fix formatting issues (like EBCDIC vs. ASCII conversions) before data moves to D365 F&O.

8. Test, Test, Test—Then Test Some More

Simulate large data volumes to ensure D365 F&O remains responsive. If the system crawls under load, identify optimizations such as indexing or query changes.

9. Going Live with D365 F&O: Final Checks & Governance

Schedule final or incremental data loads to minimize business disruption. Validate that ledger entries, open orders, and inventory balances match your expectations.

10. Archival & Long-Term Access to Legacy Data

Keep older records in a secure location—cloud-based or on-premise—to satisfy regulatory needs and provide an audit trail.

Whether you’re migrating from JD Edwards, Oracle, or NetSuite into Dynamics 365 or Dynamics CRM, the journey hinges on thorough planning and execution. By engaging your reporting teams early, maintaining a pristine master copy of extracted data, and performing transformations in a staging environment, you’ll reduce surprises and boost confidence at go-live.

✓ Sync and Automation
✓ Version-Control Everything
✓ Delta Loads
✓ Streamline Business Operations
✓ Scalability

By adopting a systematic, well-tested strategy, your AS400 or JD Edwards data can find a new home in D365 F&O—providing the historical continuity, auditability, and real-time insight your organization needs to thrive.