System stalled with 23mins remaining of El Capitan installation. Will not now download again after forced restart, help?

Anti virus software, web accelerators, and net monitoring apps such as Little Snitch can interrupt downloads

Open the App Store then select Updates from the menu top of the App Store window.

See if you can click Download or Resume for El Capitan.

If not, restore OS X using OS X Recovery.

Then try downloading and installing El Capitan again.

I'm having the same problem on a late 2014 iMac Retina 5K 27-inch. I have a 4GHz Intel Core i7, 16 GB 1600 MHz DDR3, AMD Radeon R9 M295X 4096 MB

I was able to download El Capitan, but at 25 minutes remaining in the installation my screen goes grey and stays that way. I still have mouse capabilities, as I can see a black pointer on the grey screen and it moves when I move the mouse. The installation sits that way for hours and doesn't finish. I have to force shut down the computer to regain control and then it shows Yosemite with El Capitan downloaded and ready to install.

Do you mean this?

please help me too!

and now i cant access my MBP, when i restart my mbp the system will installed again! and again.

please help, how to fix it! (i dont backup my data 😟 )

ps. and i cant login with safe mode , the MBP is shutdown when i try to access with safe mode!

i need my data :/

I should add that I am able to re-download and attempt to re-install El Cap but it failed again at the same spot in the install. When my screen goes grey the whole screen is grey. There is no logo, no anything. I can move my mouse and see the pointer. I do not get an error message at any point. I have tried this 4 times now and am going to wait for a fix as I don't want to thrash my system around any more.

Can you reboot into Recovery HD (hold down Command+R keys when booting)? If so, do a disk repair.

MacBook Pro 15" boot ONCE on El Capitan.

After restart, it turns on, I get the progress bar but it does not move.

After 5 minutes or so the screen turns into See attached screen

Safe boot doesn't work. I cannot boot to recovery mode.

Booting from DVD SnowLeopard says HD LOCKED. Disk repair says it fails.