Attachment will not open automatically

[valley_girl1919]

A user is having problems automatically opening word and excel attachments in zimbra callibration suite through the web browser. The webbrowser is IE 8 and he has been able to open it fine but about a week or so ago he could not open the attachments automatically.No other users are having problems with this. This is what happens- he clicks on an attachment within the email and it brings up a window that says "Do you want to save this file or find a program online to open it" it gives the name of the file and says type of file is "unknown file type" and it gives the option to click find or save, before it would automatically recognize excel and word files and bring up a window saying open or save. It does not do this with other file types only microsoft word and excel. How can this be fixed? He has office 2007.