opening it in a term shows this
zany130@localhost ~ gnome-boxes
(gnome-boxes:7913): Gtk-WARNING **: 01:34:35.175: GtkFlowBox with a model will ignore sort and filter functions
(gnome-boxes:7913): Gtk-WARNING **: 01:34:35.176: GtkListBox with a model will ignore sort and filter functions
(gnome-boxes:7913): Gtk-WARNING **: 01:34:53.675: Calling org.gnome.SessionManager.Inhibit failed: GDBus.Error:org.gnome.SessionManager.GeneralError: Invalid inhibit flags
(gnome-boxes:7913): Boxes-WARNING **: 01:35:09.971: libvirt-machine-properties.vala:599: Failed to change storage capacity of volume 'win10' to 120041577914: Unable to resize volume storage: internal error: Child process (/usr/bin/qemu-img resize /home/zany130/.local/share/gnome-boxes/images/win10 120041577984) unexpected exit status 1: qemu-img: Could not open '/home/zany130/.local/share/gnome-boxes/images/win10': Failed to get "write" lock
Is another process using the image [/home/zany130/.local/share/gnome-boxes/images/win10]?
which is strange as I trued rebooting the computer to make sure nothing else was accessing the file