fix error in Test-AzureRmVMAEMExtension and improve error message for standard storage

Author: MSSedusch

src/ResourceManager/Compute/Commands.Compute/Extension/AEM/AEMHelper.cs

@@ -291,13 +291,21 @@ internal string GetAzureStorageKeyFromCache(string accountName)
 
         internal string GetCoreEndpoint(string storageAccountName)
         {
-            var storage = this.GetStorageAccountFromCache(storageAccountName);
-            var blobendpoint = storage.PrimaryEndpoints.Blob;
+            try
+            {
+                var storage = this.GetStorageAccountFromCache(storageAccountName);
+                var blobendpoint = storage.PrimaryEndpoints.Blob;
+                var blobUri = new Uri(blobendpoint);
 
-            var blobMatch = Regex.Match(blobendpoint, ".*?\\.blob\\.(.*)");
-            if (blobMatch.Success)
+                var blobMatch = Regex.Match(blobUri.Host, ".*?\\.blob\\.(.*)");
+                if (blobMatch.Success)
+                {
+                    return blobMatch.Groups[1].Value;
+                }
+            }
+            catch (Exception ex)
             {
-                return blobMatch.Groups[1].Value;
+                WriteWarning("Could not extract endpoint information from Azure Storage Account ({0}). Using default {1}", ex.Message, AEMExtensionConstants.AzureEndpoint);
             }
 
             WriteWarning("Could not extract endpoint information from Azure Storage Account. Using default {0}", AEMExtensionConstants.AzureEndpoint);

src/ResourceManager/Compute/Commands.Compute/Extension/AEM/SetAzureRmVMAEMExtension.cs

@@ -298,7 +298,7 @@ public override void ExecuteCmdlet()
 
                     if (wadstorage == null)
                     {
-                        this._Helper.WriteError("A Standard Storage Account is required.");
+                        this._Helper.WriteError("A standard storage account is required. Please use parameter WADStorageAccountName to specify a standard storage account you want to use for this VM.");
                         return;
                     }