Hi,
To fix the "MSSQL on Windows: Discovery error" alert message in SCOM 2019, you can try increasing the timeout or checking the permissions with the SQL team.
However, the error message you provided indicates that there is an issue with retrieving data for the request due to a timeout or the server not responding.
You may want to check the server's performance and connectivity to ensure that it is not slow or unresponsive. Additionally, you can examine the discovery data for missing objects to see if there is a permission issue or an issue with WMI.
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