Error when trying to register a windows on premise SSM agent (and missing error details)

Question

I'm new to SSM, and just wanted to set up a test agent on a windows VM. I followed the [hybrid environment tutorial](https://docs.aws.amazon.com/systems-manager/latest/userguide/systems-manager-managedinstances.html). 
It resulted in the fowwlowing error, when running the agent installation script (in the $env:ProgramData\Amazon\SSM\Logs\erros.log file):

`ERROR [processRegistration @ agent_parser.go.177] Registration failed due to error registering the instance with AWS SSM. InvalidActivation: `

As you can see, the details about the InvalidActivation are missing... What can I do to track the error ?

Answer

We just had this error occur as well, but on a LInux external instance.  Generating a new activation code and id worked fine.
I'm curious that the activation code that failed started with a `/` and also contained a `+`, the successful activation code was only `[a-z,A-Z,0-9]`

Answer

Hello

Please check the Activation Code, as the Error says the Code. is invalid. $code = **"activation-code"**, H[ow to create activation Code.](https://docs.aws.amazon.com/systems-manager/latest/userguide/sysman-managed-instance-activation.html#create-managed-instance-activation-console)

Here is the link to find the Activation https://eu-west-1.console.aws.amazon.com/systems-manager/activations/ Check for **Activation ID** and **Activation ID ** use in the CLI while running the command.

```
$code = "activation-code"
$id = "activation-id"
$region = "region"
$dir = $env:TEMP + "\ssm"
New-Item -ItemType directory -Path $dir -Force
cd $dir
(New-Object System.Net.WebClient).DownloadFile("https://amazon-ssm-$region.s3.$region.amazonaws.com/latest/windows_amd64/AmazonSSMAgentSetup.exe", $dir + "\AmazonSSMAgentSetup.exe")
Start-Process .\AmazonSSMAgentSetup.exe -ArgumentList @("/q", "/log", "install.log", "CODE=$code", "ID=$id", "REGION=$region") -Wait
Get-Content ($env:ProgramData + "\Amazon\SSM\InstanceData\registration")
Get-Service -Name "AmazonSSMAgent"
```

Answer

Activation code can be created by using the below command in AWS Cloud Shell. Running it in command line makes it more easier for saving the activation code.  When created using the console you miss capturing the Activation Code.
```
aws ssm create-activation \
  --default-instance-name MyWebServers \
  --description "Activation for Finance department webservers" \
  --iam-role service-role/AmazonEC2RunCommandRoleForManagedInstances \
  --registration-limit 10 \
  --region us-east-2 \
  --tags "Key=Department,Value=Finance"
```

Error when trying to register a windows on premise SSM agent (and missing error details)

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