That worked, thanks. I have never selected anything but overwrite for all my updates for many years and this is the first time I've ever had a problem. I will certainly uninstall from this point forward, but it seems like a very simple fix on WA's end to include a dialog box in the install package that detects a previous version, then pops and says, "the previous version must first be uninstalled. Click OK to exit".
Appreciate the help...thanks.