AADSTS700082 – Refresh Token Expired Due to Inactivity

Error: AADSTS700082 – The refresh token has expired due to inactivity

This typically occurs when the customer tenant has an MFA setting that allows "remember MFA for X days", which breaks token refresh after extended inactivity.

Cause: The “remember MFA” setting bypasses full reauthentication for a time, but Microsoft disables the refresh token after 90 days of inactivity — causing Sync 365 access to fail.

Resolution

Disable the “remember MFA for X days” setting in the customer tenant:

1. Login to the Microsoft 365 Admin Center
2. Go to Users → Multi-Factor Authentication
3. Locate the affected user(s)
4. Disable the option: "Remember MFA for X days"

Wait ~30 minutes after disabling the option and the error should clear automatically.