Instance problem

We have a school lab of Mac OSX computers which my 2 blocks of students share, one in the morning, one in the afternoon. My first block of students didn't have any problems using the emulator in the morning. However, my second block of students in the afternoon all had problems running their programs in the emulator. The error is:

"The Companion you are using was built for different instance of App Inventor. To obtain the correct companion look on the App Inventor screen under Help->Companion Information Menu".

Students in both classes don't have issues testing using their Android phones/tablets, just my second class using the emulator.

I have tried reset, and hard reset, and nothing has worked.

Is there a problem with multiple users on the same computer running the emulator? Can there be 2 different logins accessing the emulator program on the same Mac computer?

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I believe your problem may be related to the release we just put out this afternoon. I have backed the release out until I can do more debugging. I apologize for the inconvenience.

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Thanks for the quick action and quick reply. Both our classes were able to launch the emulator now in our Mac OSX lab.

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