diff --git a/src/main/groovy/pl/touk/excel/export/WebXlsxExporter.groovy b/src/main/groovy/pl/touk/excel/export/WebXlsxExporter.groovy
index 5a8fac3..5eeaa0e 100644
--- a/src/main/groovy/pl/touk/excel/export/WebXlsxExporter.groovy
+++ b/src/main/groovy/pl/touk/excel/export/WebXlsxExporter.groovy
@@ -16,7 +16,7 @@ class WebXlsxExporter extends XlsxExporter {
     }
 
     WebXlsxExporter setResponseHeaders(HttpServletResponse response) {
-        setHeaders(response, new Date().format('yyyy-MM-dd_hh-mm-ss') + filenameSuffix)
+        setHeaders(response, new Date().toString() + filenameSuffix)
     }
 
     WebXlsxExporter setResponseHeaders(HttpServletResponse response, Closure filenameClosure) {