How to force a reset on Magic Trackpad

Here's the real answer. First, turn the trackpad off. Do this by holding down the power button for five seconds; watch the light turn green, then turn off. If the green light starts flashing, then let up on the power for a second, then hold again until it turns off.

Then press the power button again and continue until the green light starts blinking -- and CONTINUE to hold the power button, causing the green light to continue to flash. Meanwhile, go to the Bluetooth preference pane (hopefully you already did this), and observe the new device appear in the panel. Click "Pair". You should be continuously holding the power button on the trackpad during this process.

Once the dialog indicates the device is paired, you can let up.

If you hold down the button for on the side of the Magic Trackpad for ~5 seconds, one of two things will happen.

1.) The light will come on and then go off

2.) The light will come on and then blink.

In the case of number 1, you've turned the trackpad off. In the case of number 2, if you continue to hold down the button the light will continue to blink and it will become discoverable in your Bluetooth setup assistant. If you continue to hold down the button through the entire wizard, you should be able to reestablish connectivity.

This is what finally worked for me.

Another problem that commonly happens:

The Magic Trackpad might be paired to a previous Mac that is still in the same room and turned on.

If that's the case, you should first remove the Magic Trackpad from the previous Mac's Bluetooth System Preferences.

But if you can't do that for some reason, there's another trick:

1. Hold down the power button on the Magic Trackpad for 5 seconds until it turns off.

2. Hold down the power button on the Magic Trackpad for another 5 seconds until the light starts flashing... BUT KEEP THE BUTTON HELD DOWN WHILE YOU TRY TO ADD IT TO YOUR NEW MAC. The act of you keeping the button held down will prevent the Magic Trackpad from falling back on communicating with the previous Mac.

This also worked for me when I needed to re-pair my TrackPad with my iMac after pairing it with another Mac that was not easily accessible.

Thanks 

:-)

I also experienced the same problems as coqui_pregunton, but resetting the magic track pad did not help. I had to go to the "Bluetooth" section of "System Preferences" and remove the trackpad from the list of bluetooth devices by clicking the "-" button. Once it was removed, I added the magic track pad back by clicking the "+" button and following the instructions. Now everything seems to be working great. Just offering this up as an alternative solution.

Thanks, Jawkat. Removing it and then re- adding it is what worked for me. I held that poor little button down longer than anyone should have to, but "connection" kept failing.

Tried that - no luck -changed batteries no luck - it just turns off after less than 5 seconds and the trackpad icon in the Settings says I don't have a trackpad!

Also tried the above, with no luck.

Mine was working fine until the batteries ran out.....

...then it wouldn't behave again when I put new ones in.

I tried removing it from the Bluetooth devices and now it never gets re-detected.

There's no obvious way of getting it to that initial flashing light stage where it has been reset and is 'trying' to pair up again.

This is clearly what's required....

...so to re-iterate the OP : can anyone please explain how to reset the trackpad?

Just to say I RESOLVED MY ISSUE

- the replacement batteries (both sets) were too flat to work in the Trackpad.

They lost their charge whilst sitting idle for months.

Sure, they could power the single light flash, but not, apparently, a more informative warning.

So if you are unable to detect your Trackpad, blame your batteries first.

Even a simple rapid triple flash warning with the green power light would have diagnosed this unambiguously.

Perhaps a firmware update could address this.

This worked perfectly for me (reset discoverability to factory).

thanks @ norg_props

my fingers where so tired of pressing that button

jawkat's approach [removing and re-creating the Bluetooth pairing] solved my problem too.

Thanks

simple, under the bluetooth settings in control panel you have + to add - to delete and the star for settings there you can select the trackpad with the old name and select "rename" and just rename it

no need to reset the trackpad , it just updates the name and your good to go

I'm using 10.8.2, and what finally worked for me was holding the trackpad button down all during the setup process. I used the Trackpad control panel (not the Bluetooth control panel), and clicked on the button labeled "Set Up Bluetooth Trackpad...". The Trackpad light went off once during this, but I kept holding the button down/re-clicked the Trackpad button quickly and it finally connected.

Prior to this, I also deleted a previous connected in the Bluetooth System Preferences panel. Having two control panels to work with the Trackpad is confusing.