Anyway, I am still unsure what caused all these problems (and we still haven't updated to El Capitan). I first thought it was the HD, but now I think maybe some other hardware problem. And maybe El Capitan could successfully be installed after I did the PRAM and NVRAM reset. Apr 01, 2016 What this means is that when you try to install Mac OS X Mavericks, Yosemite or El Capitan from any USB or external source, the certificate checking process will render your copy of the installer null and void. You will then get the error “This copy of the Install OS X Mavericks application can’t be verified. It may have been corrupted or tampered with during downloading.”.
I’m trying to sell a 2009 MacbookPro. It’s the model MacbookPro5.5 and Apple supports macOS El Capitan 10.11 as latest available version.
I’ve wiped all data from the installed SSD and had to boot from an external disk. Now I’ve got two problems:
El Capitan Cannot Be Verified By Mail
- I’ve only got a Mac with Big Sur and Apple Silicon. I cannot use the package installer from the download provided by Apple to create the installer App for El Capitan. However, I need access to the installer so that I’m able to use the createinstallmedia command.
- The 2009 MacbookPro is already wiped and has only access to the recovery mode. You cannot execute the package installer in Recovery Mode to extract the media.
Luckily I’ve found this blog post from Chris Warrick who explained how to extract the installer App from the package:
- Attach an external Disk which contains the downloaded pkg from Apple. You’ll need enough space on that Disk to extract the pkg and it needs to be writeable
- Open the Terminal from inside the Recovery Mode
- Go to the mounted volume
- Extract the package:
Now we can try to create the install media from the installer app. Make sure you’ve attach another disk which can be overwritten by the installer. In this example its named „MyBlankUSBDrive“:
The InstallESD.dmg image is missing, which we’ll need to add to the right location: Prodent intraoral camera driver.
Now we’ll have a valid installation medium which can be used to start the installer from. You can reboot from that disk and should be able to install El Capitan.
However, I’ve encountered another annoying issue which caused the installer to fail:
El Capitan Installer cannot be verified
Oh great… On to the next commands you can try from the Terminal inside the Recovery OS:
installer -pkg /Volumes/Mac OS X Install DVD/Packages/OSInstall.mpkg -target /Volumes/'XXX'
where XXX is the name of the disk you’re installing to.- Wait for the installation to say it’s complete. You will not see any sort of progress display.
Great, you’ve got El Capitan installed! Apple had some issues with certificates and people found a way to either use the above commands for installation or you’ll have to tinker with your Macs time settings so that the signature is valid again. I would have expected that Apple resigned all installers so I wouldn’t have to use these commands at all but doesn’t look like they did.
If you are trying to install a fresh copy of Mac OS X 10.11 El Captain after downloading it from the App Store and you are using a bootable USB drive, you may receive an error message right before the install kicks off.
This copy of the Install OS X El Captain application can’t be verified. It may have been corrupted or tampered with during downloading.
This error message indicates the MPKG mechanism for checking the application installer checksum (used for proving the install files are valid and from Apple) files failed. It basically means Mac OS X will not proceed installing a copy of El Captain because it can’t prove its authenticity – even if the installation is ok. You can still push forward and install Mac OS X El Captain. Follow the steps below.
Everyone Says: Check the System Time on Mac
Apparently, the system time on your Mac may be off causing the El Captain installer to think your system date is way off. This happens if your onboard motherboard battery is toasted. Check the date to ensure it’s right – follow these steps.
1. Cancel out to the installation (If you are still on your bootable image of El Captain). Go to Utilities -> Terminal.
2. Type date. If your date is correct, then proceed to the next section below. If it’s not correct, continue with these steps.
3. Set the current date and time. In Terminal, type the following command in this format shown in example below date MONTH(02)-DATE(28)-TIME(01:51pm)-YEAR(15)
Hit enter to apply the new date. It will display. Is xbox game pass on mac. Now, attempt to install El Captain. If it still fails with the same error message, proceed to next steps below.
Force Install El Captain Terminal Command
If your confident the install you just downloaded from the App Store is valid, just use Terminal to force install it. You can do this while still booted from your USB Drive or media. Follow the steps below.
1. Type the following command into Terminal, replacing with your Volume names.
2. The install should kick off and you’ll see in Terminal “installer: OS Install started”. Wait for it to complete then reboot.
If all else fails, let us know. You may actually have a corrupt copy of El Captain in the end – maybe you disconnected your USB Jump drive incorrectly causing the files to become corrupt. Try re-downloading El Captain and re-copying it to your media.
El Capitan Cannot Be Verified
Use the comments form to let us know if you have issues or found another way to bypass this error.