Microsoft has implemented critical blocking changes to the Microsoft Customer Agreement (MCA) attestation process that all Cloud Solution Provider (CSP) partners must understand and address immediately. As of January 2026, the legacy attestation methods have been retired, and new customer orders are now blocked unless proper attestation procedures are followed.

What Has Changed

In January 2026, Microsoft retired three legacy attestation methods that partners previously used to confirm customer acceptance of the Microsoft Customer Agreement:

  • The legacy MCA attestation API
  • The UX-based attestation experience in Partner Center
  • The bulk attestation tool

Following this retirement, all new customer orders are blocked unless one of two conditions is met:

  1. The customer directly accepts the MCA in the Microsoft 365 admin center portal, or
  2. The partner attests on the customer's behalf using the enhanced MCA attestation API

Why This Change Matters

The Microsoft Customer Agreement is a critical legal foundation for customer relationships in the CSP program. Proper attestation ensures that customers understand and agree to the terms under which they receive Microsoft services. The retirement of legacy attestation methods and implementation of blocking changes serve several important purposes:

Enhanced Legal Compliance: The enhanced API and direct customer acceptance methods provide better documentation and verification of customer agreement acceptance.

Improved Customer Experience: Direct customer acceptance through the Microsoft 365 admin center provides transparency and puts customers in direct control of their agreement acceptance.

Stronger Audit Trail: The new methods create more robust records of agreement acceptance, which benefits both partners and Microsoft in the event of disputes or audits.

Standardized Process: Retiring multiple legacy methods in favor of two standardized approaches reduces confusion and creates consistency across the partner ecosystem.

Partner Action Required

CSP partners must take immediate action to ensure they can continue processing new customer orders. The specific actions depend on how orders are processed:

For Partners Using API Integration

Partners who process orders through API integration must migrate to the enhanced MCA attestation API. This new API includes improved validation and documentation capabilities that ensure proper attestation procedures are followed.

The enhanced API provides several improvements over the legacy version:

  • More robust validation of attestation data
  • Better error handling and feedback
  • Improved documentation of attestation events
  • Enhanced security measures

For Partners Using Partner Center UI

Partners who primarily work through the Partner Center user interface must adopt one of two approaches:

  1. Customer Direct Acceptance: Guide customers to accept the MCA directly in the Microsoft 365 admin center. This approach provides the highest level of customer engagement and documentation.
  2. Enhanced API Attestation: Implement the enhanced MCA attestation API to attest on the customer's behalf when direct customer acceptance is not feasible.

Implementation Resources

Microsoft provides comprehensive resources to help partners implement the required changes:

Documentation

The Microsoft Learn platform includes detailed articles covering:

  • Customer acceptance procedures for MCA
  • Creating agreement records in sandbox and production environments
  • Confirming customer agreement acceptance
  • Technical implementation details for the enhanced API

FAQ Resource

Microsoft has published a comprehensive FAQ addressing common questions about the attestation enhancements, including:

  • Technical implementation guidance
  • Timeline and transition details
  • Troubleshooting common issues
  • Best practices for customer engagement

Best Practices for Customer Acceptance

Partners should consider the following best practices when implementing the new attestation procedures:

Educate Customers: Help customers understand what the Microsoft Customer Agreement is and why their acceptance is important. This education builds trust and ensures informed consent.

Streamline the Process: Integrate MCA acceptance into your standard customer onboarding workflow to make it a seamless part of the setup process.

Document Everything: Maintain clear records of how and when customers accepted the MCA, whether through direct acceptance or partner attestation.

Test Thoroughly: Use sandbox environments to test your implementation of the enhanced API before moving to production.

Monitor for Issues: Watch for any order blocking issues and address them promptly to avoid disruption to customer onboarding.

Common Scenarios and Solutions

New Customer Onboarding

For new customers, the preferred approach is to have them directly accept the MCA in the Microsoft 365 admin center as part of the initial setup process. This ensures clear documentation and customer awareness of the agreement terms.

Existing Customer New Orders

For existing customers placing new orders, verify that a valid MCA acceptance is on record. If not, obtain either direct customer acceptance or use the enhanced API for attestation.

High-Volume Scenarios

Partners processing large volumes of orders should implement the enhanced API to enable automated attestation workflows while maintaining compliance with Microsoft requirements.

Timeline and Enforcement

The blocking changes are now fully enforced. Orders that do not meet the MCA attestation requirements will be rejected, potentially causing customer service disruptions if not addressed proactively.

Partners should prioritize implementation of the required changes to avoid order processing issues. This is particularly critical for partners with significant order volumes or those in high-growth phases where order blocking could substantially impact business operations.

Getting Help

Partners experiencing challenges with the new attestation requirements can access support through several channels:

  • Review the comprehensive documentation on Microsoft Learn
  • Consult the MCA attestation enhancement FAQ
  • Submit support requests through Partner Center for technical assistance
  • Engage with Microsoft partner support for implementation guidance

Looking Ahead

This change represents Microsoft's ongoing commitment to improving compliance, transparency, and customer experience in the CSP program. While the transition requires partner action, the enhanced methods provide better long-term outcomes for partners, customers, and Microsoft.

Partners should view this change as an opportunity to strengthen their customer onboarding processes and ensure clear documentation of customer agreements. The enhanced methods provide better protection and clearer records that benefit all parties involved.

For immediate access to implementation resources, partners should visit the Microsoft Learn documentation for customer acceptance and MCA attestation, and review the detailed FAQ covering attestation enhancements.