Excel authentication token reuse for access to Log Analytics

This behavior is intentional. Excel’s Power Query connectors, including the Log Analytics connector, manage authentication on a per‑connection basis rather than at the workbook level. When an authentication token expires, each query connection initiates its own renewal process, which results in repeated sign‑in prompts across multiple worksheets. The workaround you identified closing and reopening Excel effectively resets all connections so they can share the newly refreshed token. However, within an active workbook session, Excel does not support native reuse of a renewed token across multiple queries.

https://learn.microsoft.com/en-us/power-query/connector-authentication

https://learn.microsoft.com/nb-no/azure/azure-monitor/logs/log-excel