On cold boot or restart of my computer, I keep getting the windows " Open with" window for Registration Myst V. On original install, chose Register later. After the 3rd time this window came up, chose Never register. After the 5th time, uninstalled Myst V but that didn't get rid of it. Re-installed and Registered on Ubisoft site, and the darn "Open with" window still pops up on restart. How do I get rid of this?
Thanks.

Try the following:
-- a. Using Windows Explorer, browse to \Program Files\Ubisoft\Cyan Worlds\Myst V End Of Ages\register, and double-click on RegistrationReminder.exe to run it. Click on Never register, then on OK.
-- b. Rename RegistrationReminder.exe to something like OLD_RegistrationReminder.exe, and close Windows Explorer back to the Desktop.
-- c. Use the System Configuration utility to check for and remove a startup listing. (See How to troubleshoot by using the System Configuration utility in Windows XP for details.)
----- 1. Click on Start > Run, and type msconfig.exe in the Open: box.
----- 2. Click on OK to run the program.
----- 3. Click on the Startup tab and look in the list for a Myst V Registration entry.
----- 4. If you find a Myst V Registration entry, un-check the box, click on Apply, and then on OK.
----- 5. Reboot.