macOS Sierra downloaded, but then disappears I tried downloading macOS Sierra in the App Store. The download seems to be successful, but then the installation never happens. One solution I saw is to look for "Install macOS Sierra" in Applications, but it is not there. It's in Applications while it's downloading, so it should be there when it's done. I tried searching with Spotlight just to be sure and got no hits. The macOS Sierra App Store page says "Download" instead of "Downloaded". It's like the download never happened. Restarting and repeating did not solve the issue. Any idea what might be wrong?

What's really strange is if I go to System Information > Software > Installations, it's there, so it really was downloaded:
Start up with safe mode and then try to download and install. Here is how to enter into Safe Mode.

I have same problem and succeed to upgrade to Sierra in Safe Mode.

Good luck!