diff --git a/WEBSERVICES/ZUGFeRDRESTService/Controllers/ValidationController.cs b/WEBSERVICES/ZUGFeRDRESTService/Controllers/ValidationController.cs
index e186c6fc..e2cec04a 100644
--- a/WEBSERVICES/ZUGFeRDRESTService/Controllers/ValidationController.cs
+++ b/WEBSERVICES/ZUGFeRDRESTService/Controllers/ValidationController.cs
@@ -84,7 +84,8 @@ namespace ZUGFeRDRESTService.Controllers
                 {
                     _logger.Info("Checking Filesize of file [{0}]", file.FileName);
 
-                    bool oFileSizeIsOK = _file.TestFileSizeIsLessThanMaxFileSize(file.FileName, _MaxFileSizeInMegabytes);
+                    long maxFileSize = _MaxFileSizeInMegabytes * 1024 * 1024;
+                    bool oFileSizeIsOK = file.Length < maxFileSize;
 
                     if (oFileSizeIsOK == false)
                     {