Follow the steps below if you receive the error message 'Provided user account cannot query WMI. Check the provided account has “Read Security” level of access to WMI on the target machine. SQL Monitor is unable to monitor without access to WMI.'
Firstly check the required permissions: https://documentation.red-gate.com/sm9/getting-started/requirements/permissions
The monitoring account should administrator, although can be setup with a non-admin account, follow the instructions under 'Monitoring host Windows machines without admin permissions' from the link above. When monitoring host Windows machines the account should be an administrator on the remote Windows host machine and should have login rights locally on the machine where the base monitor is installed.
You can then test WMI. You can find out how to do so here: https://documentation.red-gate.com/sm9/advanced-operations/testing-data-collection-methods.