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Question: What is the OS upgrade helper tool?

Can I download it manually from somewhere / somehow? mentions:

"You may be asked to sign in with an administrator name and password to install a helper tool, then click Add Helper to continue."

I'm getting the following error:

Error: -[OSISClient prepareOSInstaller:error:]_block_invoke, Couldn’t communicate with a helper application.

MacBook Pro (Retina, 15-inch, Late 2013), OS X Mavericks (10.9.5), 2.6GHz IntelCorei7; 8GB1600MHzDDR3;

Posted on


Feb 28, 2018 1:53 PM in response to TJT263 In response to TJT263

Hello TJT263,

Thanks for that info and choosing the Apple Support Communities. If I understand correctly, you are unable to update the software on your MacBook Pro as you're getting an error about the helper application. To help with your situation, use safe mode to start up your Mac as it does the following things:

  • Verifies your startup disk and attempts to repair directory issues, if needed
  • Loads only required kernel extensions
  • Prevents startup items and login items from opening automatically
  • Disables user-installed fonts
  • Deletes font caches, kernel cache, and other system cache files

Log into your user account and test the issue while in safe mode by trying to update again.

Use safe mode to isolate issues with your Mac
Limited graphics performance in OS X recovery or safe mode


Feb 28, 2018 1:53 PM

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Mar 1, 2018 4:00 AM in response to MoonJ. In response to MoonJ.

Same problem. It's a fresh install by the way.

So anyway, I can probably troubleshoot it on my own.

Can you tell me anything about the helper application?

When running the installer, I notice a new process called


I assumed that was it. But that doesn't really help because it seems to be working.


Mar 1, 2018 4:00 AM

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Question: What is the OS upgrade helper tool?