I've recently discovered one thing that stops OS X USB tethering from working with Android.

For a while it was really unreliable for me, sometimes it would work and sometimes it wouldn't.

I've found that it was because I had an app called Juice Defender installed on my phone. This app is very good at saving battery life but it does so by switching your phone's data mode off and on according to a set of rules that you specify.

I found that when I uninstalled Juice Defender it was no longer controlling the way my phone connected to the network and therefore Android was able to tether with OS X more reliably.

Obviously this will only be of any use to you if you happen to have Juice Defender installed. Apart from this discovery I'm sorry to say I can't think of anything else to suggest.

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