Using Microsoft Windows

• 1). Point your Internet browser to "Support.Microsoft.com/kb/938810/." Scroll to the middle of the page to find a link that downloads a file to enable blocked Excel file types (the .wk4 type is one of them). Click on the link to save the file.
  
  
• 2). Choose where to save the file. Browse through your computer folder until you find the file save location. Click the "Save" button.
  
  
• 3). Locate the file on your computer. Double-click the file to begin the installation. This file will change some of the computer's registry values.
  
  
• 4). Open Excel. Click on the "File" menu and select "Open." Click on the pull-down menu next to "File Type." You should see ".wk4" as an option. Browse through your computer to find the "wk4" file, click to select it and click "Open."
  
  
• 5). Click on the "File" menu once the file has opened. Click on "Save As." Click on the pull-down menu, choose "Xls" from your file options and click the "Save" button. The file is now saved with the "Xls" format.