Windows Taskbar - Prevent some applications from grouping?

This probably applies to either Vista or Windows 7...they both have a feature where it will group windows from the same app under a single button. However I have one application I want it to never group -- specifically an X11 server, where different windows are separate apps and not related (ie, I don't want it grouping my xterm window along with my accounting software window, just because they are both owned by xserver.exe).

I don't want to turn it completely off, I like when it groups all my Explorer windows together for example. I just want to exclude/whitelist/? a single application, xserver.exe, from having its windows grouped.

Solution 1:

7 Taskbar Tweaker should do exactly what you want:

This programs enables you to tweak your Windows 7 taskbar. The tweaks are divided into three sections:
Taskbar items: control taskbar items related stuff, like middle/right clicking, hovering, dropping, etc.
Grouping and combining: disable grouping, allow to drag windows between groups, force/disable combining, etc.
Other taskbar options: mouse wheel options, double/middle clicking on the empty space of the taskbar, and misc.

Answer

To prevent only some applications from grouping in the Taskbar, using Task Tweaker, follow the instructions in the following screenshot. In this example, I am configuring it to prevent Outlook from grouping: