I use a file manager called PowerDesk8. I found 54 instances of evernote.msi in various ApplicationData folders. They were all dated 9/19/2010 and were each 43,736,576 bytes in size. I removed them all then re ran the 4.1 installer and everything proceeded as expected. Now... how do I get the WebClipper add on in Firefox to function? I have uninstalled it - restarted Firefox and, in theory, reinstalled it; but the button is not showing up on the toolbar. Thanks in advance... ~L