Inno Setup: Disable components page on upgrade

Question

Is there a way to disable the Components Page for Upgrades? I would like to enable upgrades of my software but I don\'t want to allow the users to change the selection of co

Answer 1

The IsUpgrade function mentioned in TLama's answer has a bug. If AppId starts with a "{" which must be doubled, this isn't resolved and they registry key will not be found. Here's a corrected function that works for me:

function IsUpgrade: Boolean;
var
    Value: string;
    UninstallKey: string;
begin
    UninstallKey := 'Software\Microsoft\Windows\CurrentVersion\Uninstall\' +
        ExpandConstant('{#SetupSetting("AppId")}') + '_is1';
    Result := (RegQueryStringValue(HKLM, UninstallKey, 'UninstallString', Value) or
        RegQueryStringValue(HKCU, UninstallKey, 'UninstallString', Value)) and (Value <> '');
end;

Leave the separate const away for this function, it won't work with that extra function call.

Apart from that, 64-bit systems don't seem to cause any issues. If InnoSetup runs in 32-bit mode, the registry virtualisation is in effect and redirects you to the correct key already.