I can access my gnome desktop from another pc using vnc. However when I try to open, for example, a spreadsheet it opens on my main desktop on the computer itself instead of my remote session.

Here is my xstartup:
#!/bin/sh

# Uncomment the following two lines for normal desktop:
unset SESSION_MANAGER
exec /etc/X11/xinit/xinitrc

[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &
xterm -geometry 80x24+10+10 -ls -title "$VNCDESKTOP top" &
twm &a
#unset SESSION_MANAGER
#exec /etc/X11/xdm/Xsession gnome

Thanks for the help.

I was thinking that it was in the line that unsets the session manager but when I comment that line out and start vncserver I just get a blank screen on the remote session

When you say that you open a spreadsheet, is this spreadsheet located on your local or remote machine?

If you open a file using the local filemanager it will launch locally. If you open a file using the filemanager running on that remote machine, it will launch remotely.

think of a VNC session as very long keyboard video and mouse cables running to the remote machine, it only allows you to control the remote PC, there is no other interaction between the local and remote machines.

Here is what is happening. I have vncserver starting at boot. It seems to take the "main" session because when I view that remote session it has my custom themes.
When I log directly into the pc, that session does not have my custom theme. In fact I try to apply my custom theme to my local session and it will not change.

I killed the vncserver service and my custom theme applied to my local session. And then I restart vncserver and the default look is now on the remote session.

Why is this happening and how can I fix.