diff --git a/datastore_server/source/java/ch/systemsx/cisd/openbis/dss/generic/server/Utils.java b/datastore_server/source/java/ch/systemsx/cisd/openbis/dss/generic/server/Utils.java
index 5a28f48ae250009158b1ae92390a9b5f2e0b1ce4..b7b35905d1bdafc6846c31bfba348b74e70a4c0f 100644
--- a/datastore_server/source/java/ch/systemsx/cisd/openbis/dss/generic/server/Utils.java
+++ b/datastore_server/source/java/ch/systemsx/cisd/openbis/dss/generic/server/Utils.java
@@ -44,6 +44,8 @@ public class Utils
     {
         MIMETYPES.addMimeTypes("application/pdf pdf");
         MIMETYPES.addMimeTypes("image/svg+xml svg");
+        MIMETYPES.addMimeTypes("video/webm webm");
+        MIMETYPES.addMimeTypes("video/mp4 mp4");
     }
     
     static String createUrlParameterForSessionId(String prefix, String sessionIdOrNull)