Cannot start Mac Book Pro after failed install of E Capitan

[jake25iuk]

Hi, a friend brought round his mac book pro which was stuck in recovery mode and would not install the os (yosemite).
He said he wanted it wiping as he was going to give it to his son. I created a bootable el capitan usb disk using my mac downloading the installer from the app store. This seemed to work fine, the mac saw the drive and the install seemed to be working fine, it got to where the installer says "about one second left" but then failed and showed the error "This copy of the Install OS X El Capitan application can't be verified. It may have been corrupted or tampered with during downloading".
Now it will not start up, when the usb drive is plugged in the apple logo appears with the loading bar and this gets about 3/4 and then stays there, without the usb drive in i get a folder with a question mark flashing. I cannot open the mac in recovery/safe mode and when I open holding option i only get the option to select the usb drive (no mac hd) .. when i choose the usb drive it just gets stuck on the apple loading screen again.

Any help would be much appreciated. Thanks. Jake.

 

[Cory Cooper]

Hello and welcome.

-Which exact model of MacBook Pro?
-What steps did you use to create the USB installer?

You could try this to create a new USB installer and try the install again: DiskMaker X

C

 

[jake25iuk]

Hello and welcome.

-Which exact model of MacBook Pro?
-What steps did you use to create the USB installer?

You could try this to create a new USB installer and try the install again: DiskMaker X

C

Thanks, i will try this, i am at work at the moment and am not sure wich model, i think its the last one that had a cd drive. i will look later and post back. My main concern is why the usb drive seemed to work first but now cannot start, is the hard drive damaged by the failed install? i really want to get on to dusk utility but cannot.

 

[jake25iuk]

Thanks, i will try this, i am at work at the moment and am not sure wich model, i think its the last one that had a cd drive. i will look later and post back. My main concern is why the usb drive seemed to work first but now cannot start, is the hard drive damaged by the failed install? i really want to get on to dusk utility but cannot.

I used terminal to create the bootable usb drive, i have done this before with sucess to my own mac

 

[jake25iuk]

Hello and welcome.

-Which exact model of MacBook Pro?
-What steps did you use to create the USB installer?

You could try this to create a new USB installer and try the install again: DiskMaker X

C

Ok I have looked but do not know what model it is without swiching it on, I tried to make a bootable usb drive using ."diskcreater x" and it said it worked and the mac book saw the drive (this time the icon was different) but the mac book will still not start from it, still 3/4 of the loading bar and it just stays there. Thanks

 

[Cory Cooper]

OK...

-You can get the exact model by entering the serial number here: Check Your Service and Support Coverage
-We need to ensure that it is compatible with El Capitan
-Did you install any third-party RAM in your Mac?

C