Wireless keyboard which is running over Bluetooth connection is sometimes causing slow recognition at the booting time. In some cases it takes at least two or three minutes which is so long to the urgent needs of computer use.
Therefore we should wait at the login password prompt in Windows booting screen.
To clear out this problem, I searched Internet and found several methods which are proved to be failed one.
In the manufacturer's homepage such as Logitech, they recommend reinstalling the driver of wireless keyboard with the new one other than the default Windows driver. But this doesn't fix the slow recognition problem.
Other possible solution was relocating USB port of the receiver to the higher priority one so that wireless keyboard is firstly run. Another solution was blocking possible conflict among USB devices which is just inserting only wireless keyboard receiver. But these methods were also failed.
Finally I fixed this problem by eliminating automatically started software
and services at the booting time. Those are computer vaccine drivers,
software update engines, messaging app. drivers, etc.
The method to eliminate non-essential service and startup software is as follows.
To do this, just run 'msconfig.exe' which is Windows configuration software. You can run this by searching it at the 'Start' button screen as shown in below.
You can also run 'msconfig.exe' at the 'MS-DOS command prompt'.
on 'msconfig.exe', do clicking 'Services' tab, and checking 'Hide all Microsoft services' and clicking 'Disable all'. This makes all of Non-Microsoft service stop running at the booting time.
Now do clicking 'Startup' tab, and checking 'Disable all'. This also makes all of non-Microsoft service are not running at the booting time. You can also exclude some essential one by clearing the check.
Through these elimination process, slow recognition of wireless keyboard at the booting time was not happened again. Now wireless keyboard is responding immediately.
Even non-Microsoft service and program is stop, it could be run after booting. If somethig should be started, you can include it.
I hope this method is helpful who has been affected on this matter. Good day of all.