How can I set a Magic Trackpad (or, any other bluetooth device, I guess) into discovery mode, if it has already been paired to another mac?
Anything I find on google just mocks me.
(I took the Magic Trackpad for example, but it applies to Apple Bluetooth keyboard and Magic Mouse as well)
When you start a Magic Trackpad, it announces itself over bluetooth :
So, one Magic Trackpad can be paired to multiple computers. When you start it, the first computer to connect to it get it (first arrived, first served).
If you have two Macs next to each other (A & B), your Magic Trackpad paired to A and you want to pair it with B, you have four choices :
Once done, you can start a new pairing procedure on B.
I hope it answers to your question.
(you can also stop and start again your Magic Trackpad while detecting new bluetooth devices on B and hope B will find it faster than A, but you'll probably need to make that several times before getting it to work)
I just did this. You put your trackpad or keyboard into discovery mode by holding the power key until the green light is blinking. The mac mini recognizes the trackpad almost immediately, and then walks you through the process of connecting your keyboard. Keyboard does not need to be in discovery mode, only needs to be powered on.
Took 2 min, very simple. Don't waste any money or space on a USB keyboard!
I don't think the magic trackpad (or the magic mouse) have a "discovery mode." Just make sure the bluetooth on the Mac it was previously paired to is off, then go about connecting it to the new Mac as normal.