I'm using Drupal 7.x with the Views Data Export (7.x-3.0-beta7) module to provide Excel file downloads of view data I've created. With it I can output a simple link, that when clicked on, provides a direct download of the Excel file consisting of the view data. It's pretty cool. The module basically does what it's supposed to do except that the following message is displayed when trying to open the XLS files:

The file you are trying to open, 'filename.xls.xls', is in a different format than specified by the file extension. Verify that the file is not corrupted and is from a trusted source before opening the file. Do you want to open the file now?
This happens on both XP machines and Windows 7 machines...

In the above message, "filename" appears as if it's hashed (i.e. - it looks like encrypted text and is about 8 or 9 characters in length--this time, it was "i7P8vU9O"). I'm not sure why "xls" is showing twice but it's not from anything I've done. This message-window has 3 buttons: "Yes", "No", and "Help" and if I click on "Yes", the Excel file opens perfectly fine in Excel...

I'd like to fix the issue thought if possible... Any ideas what's causing it? I might be wrong here but after scouring the module's code, I found what I believe are the headers that are being sent:

meta http-equiv="Content-Type" content="application/vnd.ms-excel" 
meta http-equiv="Content-Type" content="text/html; charset=utf-8"