When you use Azure DevOps to deploy your projects you can connect it to Azure via different methods. The most convenient type of service connection is `Azure Resource Manager using service principal authentication`.
This type of connection creates application in your Azure Active Directory which is used as a Service Principal. Then for this application secret is generated, so Azure DevOps can connect to Azure. This secret token is expiring from time to time. The default time to live is 2 years but it may vary.
Once the secret is expired you will get this type of error when trying to deploy your code to Azure:
##[error]Error: Failed to get resource ID for resource type 'Microsoft.Web/Sites' and resource name 'XXX'. Error: Could not fetch access token for Azure. Verify if the Service Principal used is valid and not expired. For more information refer https://aka.ms/azureappservicedeploytsg
