By the way, yes, the user needs to have administrator privileges to install or update the Meraki agent.
Ensure that the m_agent_service.exe is running on the affected devices.
Review the agent logs for any errors that might indicate why the update is failing. Logs can be found in C:\ProgramData\Meraki\Systems Manager Agent\Logs
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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