Почему сообщение об ошибке отображается правильно на локальном компьютере, а не в QA UAT и prod Machine? В чем может быть причина?

scope.uploadFile = function (fileModel) {
          Upload.upload({
              url: scope.url,
              method: 'POST',
              fields: {'requestId': scope.requestId, 'type': scope.type, 'isFileExisted' : fileModel.isFileExisted},
              file: fileModel.file,
              fileFormDataName: 'myFile',
              sendFieldsAs: scope.form
          }).progress(function (evt) {    // Progress bar.
              fileModel.completion = parseInt(100.0 * evt.loaded / evt.total);
          }).success(function (data, status, headers, config) {
              fileModel.serverMessage = 'File uploaded successfully';
              fileModel.status = '200';
              fileModel.id = data.id;
              scope.onUpload({document: data});
          }).error(function (data, status, headers, config) {
              fileModel.status = '500';
              fileModel.serverMessage =  data.errors[0].message;
              return false;
          });
        };

def validateDocument(String type, def file, def requestObj) {
        String errMsg

			if(type == 'treasury')
			{
				if (documents.findAll({ it.documentType == DocumentType.My_DOCUMENTS }).size() >= 5)
				{
					errMsg = "Maximum 5 attachments are allowed."
				}
				else if (documents.findAll{ it.documentType == DocumentType.My_DOCUMENTS }.find { it.fileName == file.originalFilename })
				{
					errMsg = "File with same name already exists."
				}
			}
	        if (file.getSize() >= (1024 * 1024 * 5))
			{
                errMsg = "File size cannot exceed 5 MB."
            } 
			else if (!(mediaType == 'application/x-tika-ooxml' || mediaType == 'application/pdf'))
			{
                errMsg = "Invalid file format. Please add .doc .docx .xls .xlsx .pdf only"
            }
			else if (file.empty) 
			{
                errMsg = "File cannot be empty."
            } 
        }
        errMsg
    }