We're currently having a problem with our 2008 SSRS server sending excel reports to users with iPhones. They get the email with no problems, but when the XLS file is opened on the phone, it returns an error of: Invalid format. Everyone else can open the report with no problems (email/blackberry)

The odd thing, is I can drag the file to my desktop from the message, open it, save it, and then email it again and it opens just fine on the phone.

Does anyone know of hotfix that can be applied to the SSRS server to create the XLS files correctly? Or something I can change to make this work?

I know we can send all the attachments in PDF but I'd like to keep them XLS if at all possible.