FWIW, in case it helps anyone & all that...
Microsoft's prime motivation behind Copilot is $$$$$ -- stock prices have been skyrocketing for companies involved in AI, which translates into money in the bank for execs. In Windows it's actually useful for stuff like spreadsheet formulas along with some biz-centric automation -- for everyday home users Microsoft envisions being able to just talk to your computer to accomplish stuff that, while easy enough, could be similar to some of the conveniences some folks are used to using their phones, e.g., "show me Sam's last 6 emails in chronological order with the newest first". It's not there yet. TO keep the illusion of momentum while we wait, Microsoft is doing IMHO dumb stuff like adding AI to Notepad, not to write anything, but to search for info and explain selected text.
That said, the article Chris linked to at The Windows Club is hit & miss -- not everything works [they've got some of the registry stuff wrong]. *To Me*, the easiest way to accomplish turning Copilot on/off is to double click a .reg file, merging it with the registry [I think it's easier than opening Settings]. Here are the contents for 4 .reg files to show/hide Copilot or turn it completely off. Two of them use Group Policy, which I've checked in Win11 Home to make sure they work [Windows Home doesn't include Group Policy] TO that end, copy/paste the following [between the ----] into a new txt file in Notepad, save it with the .reg extension, then double click to merge.
To hide the Copilot icon on the Taskbar -- takes immediate effect:
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Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
"ShowCopilotButton"=dword:00000000
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To show the Copilot icon on the Taskbar -- takes immediate effect:
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Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
"ShowCopilotButton"=dword:00000001
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To turn off Copilot entirely in Windows using Group Policy -- requires restart:
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Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\WindowsCopilot]
"TurnOffWindowsCopilot"=dword:00000001
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To turn on Copilot in Windows using Group Policy -- requires restart:
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Windows Registry Editor Version 5.00
[-HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\WindowsCopilot]
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Note: these registry entries or values may or may not work in the future as Microsoft updates Win11.