Magic trackpad hangs on user switching

Kind of. I just restarted my computer a number of times, and for some crazy reason the problem went away. I wish I had a better answer then that, but I've been unable to recreate the issue since about 48 hours after my above post.

Also having this exact same problem. After switching between user accounts, the Magic Trackpad will not move the cursor, but it will click. Running Lion 10.7.4. Tried de-selecting "allow bluetooth devices to wake this computer" in the second user account, while keeping it in the admin account, but that didn't solve the problem. Powering the trackpad off and back on makes it work again. It's not a battery issue.

You need to de-select that "allow devices to wake computer" option in Bluetooth settings in both accounts you're switching between.

It won't completely eliminate the problem, but it will make it happen far less often.

Here's what I found over the last several weeks of using Lion: if my wife and I both made a point to close iPhoto before walking away from the computer or before the other person Fast-User-Switched over to their profile, the problem seemed to go away. I suspect iPhoto used the discrete/accelerated graphics chip, though I have no idea if that's related. Back in the day, I thought I'd noticed the same thing happening if I left Sparrow or Twitterrific open on my profile before my wife FUS'd over to her profile.

Now, we've upgraded to Mountain Lion, and I'm scared to even experiment just yet, but we've continued to be religous about keeping iPhoto closed. In the coming days and weeks on ML, we'll attempt leaving iPhoto open or maybe turning "allow bluetooth devices to wake this computer" back on and see what happens. Oh how awesome it would be to actually be able to utilize features like that and/or not worry so much about leaving iPhoto or other 3rd party apps up and running before the other user logged in!

I'll keep everyone posted as I learned anything new (in case anyone still cares about this problem).

I have found that Mountan Lion 10.8 seems to have largely fixed these problems for me. My wife and I have ceased worrying about whether iPhoto is left open or not on either of our profiles, and the problem has yet to rear its head.

The next step is to again try enabling "allow bluetooth devices to wake computer" to see if that's now fixed, too.

I'm having the same issue on Mountain Lion 10.8.2. I do not have iPhoto, for me simply clicking "Switch Account" from the lock screen causes the Magic Trackpad to stop tracking. I have plugged in another USB mouse so I can post this reply, the weird thing is if I click my Magic Trackpad, I can click just fine, so it isn't like the Trackpad lost connection, I just can't move the mouse cursor 😟 - This is very annoying and forces me to have to reboot every time this happens.

Any solution?

I pretty much don't have the problem at all anymore on Mountain Lion, regardless of whether iPhoto is open or not.

But, I still have Bluetooth devices can wake computer turned off in settings. I'm just so happy to not have the problem anymore, that I don't want to press my luck and cause the problem again.

Have you tried to click "Switch User" from the lock screen? - I mean if your screensaver is on and it's set to ask for password, there is an option to "Switch User", when I click that, my magic trackpad stops tracking, i.e. I cannot move the mouse cursor 😟

I have the Bluetooth devices can wake computer turned off also.

Count me in as one who is experiencing this exacty problem, on both Snow Leopard and now Lion.

I think I'm going to submit a support ticket.

Also on version 10.6.8 Trackpad hangs as soon as I switch user. Only a reboot sorts the problem. Massively frustrating.

I have installed Lion a few days since its release, and the problem has apparently disappeared, at least until now (fingers crossed!)

This problem only just started for me a couple of days ago.

Has there been an official response/fix from Apple?

Not that I'm aware of.

Did you make any recent changes that prompted the problem? Did you try my workaround?

I'd like to add another "Me too…" for this problem. Trackpad disconnects when switching users.

I also experience this problem. For now, I am trying the workaround supplied by bripab007. Will report later on.