diff --git a/src/Elastic.Apm/BackendComm/BackendCommUtils.cs b/src/Elastic.Apm/BackendComm/BackendCommUtils.cs
index cb47daa17..d68a04db6 100644
--- a/src/Elastic.Apm/BackendComm/BackendCommUtils.cs
+++ b/src/Elastic.Apm/BackendComm/BackendCommUtils.cs
@@ -270,9 +270,9 @@ internal static HttpClient BuildHttpClient(IApmLogger loggerArg, IConfiguration
 				}
 			}
 
-			if (configuration.ApiKey != null)
+			if (!string.IsNullOrEmpty(configuration.ApiKey))
 				httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("ApiKey", configuration.ApiKey);
-			else if (configuration.SecretToken != null)
+			else if (!string.IsNullOrEmpty(configuration.SecretToken))
 				httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", configuration.SecretToken);
 
 			return httpClient;