Hi Giancarlo
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
Check your application can connect to Azure Monitor without problems.
Check that the credentials have the right permissions to send data to Azure Monitor. A 403-error means access is denied.
https://learn.microsoft.com/sr-cyrl-rs/azure/azure-monitor/logs/api/errors
Check that your connection string is correct and valid.
Ensure the Azure resource you're sending data to has the right permissions, and that your connection string is linked to a valid Azure Monitor or Application Insights resource.
If you are using an agent (like the Azure Monitor Agent), check its status and logs for errors that could show connection issues with Azure services.
https://learn.microsoft.com/en-us/azure/azure-monitor/agents/agent-windows-troubleshoot?tabs=UpdateMMA
https://learn.microsoft.com/en-us/azure/azure-monitor/agents/azure-monitor-agent-troubleshoot-windows-vm
If you have any further queries, do let us know.
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