edit per @jluk

Author: ktoliver

articles/aks/troubleshooting.md

@@ -112,7 +112,7 @@ Follow the *Before you begin* steps in the appropriate doc to correctly register
 
 Naming restrictions are implemented by both the Azure platform and AKS. If a resource name or parameter breaks one of these restrictions, an error is returned that asks you provide a different input. The following common naming guidelines apply:
 
-* The hard limit for cluster name is 1-63 characters and can only contain letters, numbers, dash and underscore are allowed in middle.
+* Cluster names must be 1-63 characters. The only allowed characters are letters, numbers, dashes, and underscores. The first and last characters must be a letter or a number.
 * The AKS *MC_* resource group name combines resource group name and resource name. The auto-generated syntax of `MC_resourceGroupName_resourceName_AzureRegion` must be no greater than 80 chars. If needed, reduce the length of your resource group name or AKS cluster name.
 * The *dnsPrefix* must start and end with alphanumeric values. Valid characters include alphanumeric values and hyphens (-). The *dnsPrefix* can't include special characters such as a period (.).
 
@@ -126,4 +126,4 @@ Based on the output of the cluster status:
 
 * If the cluster is in any provisioning state other than *Succeeded* or *Failed*, wait until the operation (*Upgrading / Updating / Creating / Scaling / Deleting / Migrating*) terminates. When the previous operation has completed, re-try your latest cluster operation.
 
-* If the cluster has a failed upgrade, follow the steps outlined [I'm receiving errors that my cluster is in failed state and upgrading or scaling will not work until it is fixed](#im-receiving-errors-that-my-cluster-is-in-failed-state-and-upgrading-or-scaling-will-not-work-until-it-is-fixed).
+* If the cluster has a failed upgrade, follow the steps outlined [I'm receiving errors that my cluster is in failed state and upgrading or scaling will not work until it is fixed](#im-receiving-errors-that-my-cluster-is-in-failed-state-and-upgrading-or-scaling-will-not-work-until-it-is-fixed).