Office Documents Save as Zip Files
Internet Explorer 8 downloads Office 2007 or Office 2010 files as zip files instead of the correct file format. Double-clicking the file extracts the contents into a folder which contains files Office cannot open.
Office 2007 and above save their files in a zipped format. While the file has an extension of .docx, .xlsx, or .pptx, Internet Explorer 8 interprets the file as a .zip file and attaches that extension to the download.
SolutionsIf you have to (or want to) continue using IE8
1. In the upper-right corner of IE8, click on Tools to open the drop down menu;
2. At the bottom of the Tools menu, click Internet Options;
3. In the Internet Options dialog box, select the Security tab;
4. On the Security tab, select the Internet zone, then click the Custom Level button;
5. Scroll about 2/3 down the list to the option "Open file based on content, not file extension" and change the setting to Disable;
6. Click OK;
7. Repeat steps 4-6 for the Local Intranet zone and Trusted Sites zone;
8. Click OK;
9. Close all instances of IE8;
10. Reopen IE8 and it should now recognize Office 2007 and 2010 file extensions when saving email attachments.
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