After you apply this fix and set the BypassOwaHTMLAttachmentFiltering option to True, you have to set the file name extensions of the HTML attachments in the Force Savelist. To do this, follow these steps:
- In the Exchange Management Console, click Server Configuration, and then click Client Access.
- In the action pane, under Outlook Web Access, click Properties.
- Click either the Public Computer File Access tab or the Private Computer File Access tab.
- Under Direct file access, select the check box next to Enable direct file access to enable users to download attachments.
- Click Customize next to Customize direct file access to change the type of attachments that you want users to be able to access.
- On the Direct File Access Settings page, click Force Save. Then, set the .xls file name extensions in the Enter the file extensions you want to force save, one at a time dialog box on the Force Save List page, and then click Add.
- Click OK three times to save your settings.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
All HTML content in attachment files of messages is run through an HTML filter when you open or save the attachment by using Outlook Web Access (OWA)