you need to tell your computer to open TIF files in Elements.

Open Explorer, then up the top menu in explorer, click on Tools, folder options, select the file types tab. scroll down the list till you find the extensions (TIF and TIFF).

Click on them, then click the "change" button, find elements and set that as the default for both TIF and TIFF.

Then see how you go.

*note following these instructions is at your own risk*