The Windows installer should notify the user and provide a copy of the GPL. It is not necessary, and in fact runs contrary to the text in the licence, to accept the licence simply to run copies of the code.
To quote clause 9 of the GPL " 9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or
run a copy of the Program. [...] However,
nothing other than this License grants you permission to propagate or
modify any covered work. These actions infringe copyright if you do
not accept this License. Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so."
The Windows installer should notify the user and provide a copy of the GPL. It is not necessary, and in fact runs contrary to the text in the licence, to accept the licence simply to run copies of the code.
To quote clause 9 of the GPL " 9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy of the Program. [...] However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so."