Okay I have figured this out myself with some research. For anyone with similar problems: The extra authentication prompt with certain MS Office files is because the MS Office application attempts to open the file directly on the server. See http://support.microsoft.com/kb/2019105. The user needs to download a copy (e.g. right click-save as) if they don't have credentials on the server. The incorrect file extension issue is a result of missing MIME types on the web server. How they are added depends on the web server. See http://www.webdeveloper.com/forum/showthread.php?162526-Is-your-docx-file-tu... for a list of MIME types to add for new MS Office files. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Christian Fiddick Sent: Monday, October 14, 2013 11:41 AM To: [email protected] Subject: [xwiki-users] Excel file attachment problems Hi all, I have my XWiki 5.1 deployment set up to store attachments in the file system (not database). If for e.g. I upload a docx file as an attachment and download it, it all works fine. If I upload a Microsoft Excel file (xlsx, xlsb, xlsm, etc.) it attaches fine, but opening presents a few strange problems. If it is a plain xlsx file, clicking open instead of save when downloading the attachment prompts me to enter a server password. If I click save, it downloads and I can open it fine. For xlsb and xlsm files, the attached file is served as a .zip file... I have no clue why. It's like this in any browser I try. I'm not sure where the problem lies. Any ideas? Thanks. _______________________________________________ users mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/users