Microsoft is deprecating Basic Authentication for several Exchange Online protocols, including Exchange Web Services (EWS) and Exchange ActiveSync (EAS), in favor of the more secure, token-based OAuth 2.0 Modern Authentication. This transition is driven by security concerns, as Basic Authentication relies on username and password credentials which can be vulnerable if not properly secured, whereas OAuth 2.0 uses tokens that offer more control and granularity over access. The timeline for this shift has been adjusted due to the COVID-19 pandemic, with existing tenants receiving indefinite support until further notice, while new or inactive tenants have Basic Authentication disabled by default since October 2020. Nylas offers APIs that facilitate this transition by providing seamless integration with various email, calendar, and contact providers, reducing both development time and costs. The company is committed to supporting its customers through the transition, offering resources and guidance to optimize security and data access with their integration offerings.