09-12-2016, 02:26 AM
I don't think that's grub issue. Might be due to age of computer (if particularly old). Though I've just tested using wireless mouse/keyboard combo on a 2002 Pentium 4 machine and it does work during boot-up, so that might not be it. (Can hit the left-SHIFT key during boot to invoke grub menu and can manoeuvre in the menu with up/down arrow keys.) I've got a different computer (~4yrs. old) hooked-up to my TV that I've had set-up with wireless mouse/keyboard combo from the start. That works fine in grub too.
A wild guess might be that only certain USB ports are immediately recognized during boot and others may not be initialized until OS gets loaded. Try plugging the wireless USB receiver into different ports -- particularly the ones on the back of computer instead of front.
A wild guess might be that only certain USB ports are immediately recognized during boot and others may not be initialized until OS gets loaded. Try plugging the wireless USB receiver into different ports -- particularly the ones on the back of computer instead of front.
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