Why is IE7 saving the MS Excel file as a zip file?

My company has an internal portal for our staffs. We sometimes attach Microsoft Excel files for people to download. When using Firefox or chrome, if someone clicks on the link, it downloads as an excel file, but on IE7, it is downloaded as a zip file…How can i solve this problem?

Thank you

Check your servers are setup correctly regarding MIME and look for hidden file extensions; I assume you mean you have a *.xls file that for some weird reason downloads as *.zip in IE7.

The file is in a .xlsx format (Microsoft Excel 2007 format). What i did was save it as Excel 2003 .xls format, and now it doesn’t save as a zip file. Guess this is a quick fix