hi, the writer tool will be part of the windows live essentials program. please refer to microsoft's documentation on how to uninstall programs: http://windows.microsoft.com/en-us/windows-10/repair-or-remove-programs

You can uninstall Windows Live Writer from your computer by using the Add/Remove Program feature in the Window's Control Panel.

On the Start menu (for Windows 8, right-click the screen's bottom-left corner), click Control Panel, and then, under Programs, do one of the following:

Windows Vista/7/8: Click Uninstall a Program. Windows XP: Click Add or Remove Programs.

When you find the program Windows Live Writer, click it, and then do one of the following:

Windows Vista/7/8: Click Uninstall. Windows XP: Click the Remove or Change/Remove tab (to the right of the program).

Follow the prompts. A progress bar shows you how long it will take to remove Windows Live Writer.

If the steps above don't help, please try using an advanced uninstaller to forcibly uninstall it from your PC.