diff --git a/config/alfresco/web-client-config.xml b/config/alfresco/web-client-config.xml
index b916d6f248..ec4f55faa0 100644
--- a/config/alfresco/web-client-config.xml
+++ b/config/alfresco/web-client-config.xml
@@ -404,8 +404,8 @@
          <transformer name="image/gif"/>
          <transformer name="image/jpeg"/>
          <transformer name="application/msword"/>
-         <transformer name="application/vnd.excel"/>
-         <transformer name="application/vnd.powerpoint"/>
+         <transformer name="application/vnd.ms-excel"/>
+         <transformer name="application/vnd.ms-powerpoint"/>
       </transformers>
       <image-transformers>
          <transformer name="image/gif"/>
diff --git a/source/java/org/alfresco/web/app/servlet/BaseDownloadContentServlet.java b/source/java/org/alfresco/web/app/servlet/BaseDownloadContentServlet.java
index 45a1da45a5..cd8125b7f5 100644
--- a/source/java/org/alfresco/web/app/servlet/BaseDownloadContentServlet.java
+++ b/source/java/org/alfresco/web/app/servlet/BaseDownloadContentServlet.java
@@ -72,7 +72,7 @@ public abstract class BaseDownloadContentServlet extends BaseServlet
 
    private static final long serialVersionUID = -4558907921887235967L;
    
-   private static final String POWER_POINT_DOCUMENT_MIMETYPE = "application/vnd.powerpoint";
+   private static final String POWER_POINT_DOCUMENT_MIMETYPE = "application/vnd.ms-powerpoint";
    private static final String POWER_POINT_2007_DOCUMENT_MIMETYPE = "application/vnd.openxmlformats-officedocument.presentationml.presentation";
    
    private static final String MULTIPART_BYTERANGES_BOUNDRY = "<ALF4558907921887235966L>";