Implementing Microsoft Dynamics 365 Sales involves several key challenges. Data migration is complex, often leading to potential data loss or corruption if not handled carefully. Integrating the platform with existing systems requires significant customization, which can be time-consuming and costly. Ensuring user adoption is another hurdle, as resistance to change and insufficient training can impede smooth transitions. Additionally, maintaining robust data security and regulatory compliance adds to the difficulty. Finally, providing continuous support and swiftly addressing technical issues is essential to avoid disruptions in sales operations.