The error message "error":"instance_id cannot be blank" is presented when we are unable to obtain the instance id from AWS.
Instances are provided by AWS through a call on a subnet to the 'AWS Instance metadata service' and Instance IDs are written within the JSON file along with performance data. Often this error exhibits itself in machines with complex network configurations (multiple NICs), if there are lots of redirects (especially if long hops), or generally slow networks & firewalls. To troubleshoot:
1. Open the Windows Service Manager and stop the CloudHealth Agent
2. Clear out the C:/Windows/system32/config/systemprofile/appdata/perfdata folder or copy them to another location
3. Restart the agent and verify if the error is still occurring in the logs. It will likely need an hour or so of running before we start to see the population in CloudHealth.