Need re-signed X EL Capitan Installer (2022)

if you have ANY working MacOS on a Mac Mac with 10.11 El Capitan or later on it now:

Use the versions available in this article to build a new USB stick installer. Your section is the last one, labeled "use a web browser", specifically safari 9 or later:

How to download and install macOS - Apple Support

NB>> open the download to get a .dmg file

double-click to open that to provide a .pkg file

double-click that to PLACE, but what you are PLACE-ing is the MACOS INSTALLER, and where you are placing it is in the /Applications folder.

Next, the specific instructions for creating a USB stick from an "Install MacOS ..." from that Mac's /Applications folder can be found in this article. Note that the Terminal command can be triple-clicked to select it ALL, then cut and pasted to the Terminal command line, provided you named your Initialized (to any format) USB stick exactly MyVolume.

Create a bootable installer for macOS - Apple Support

El captain is about 6.2 GB image, requires a USB stick of 8 GB or larger.

AI does not know the Answers. it only knows what hundreds of others have suggested, in WILDLY different situations.

You don't modify the date of the download, because that is not the issue.

If your Mac System Time chip has not been set to a time within five minutes of internet time, that date will not be good enough, and ALL encryption situations will fail with messages like “This copy of the Install OS X El Capitan application can't be verified. It may have been corrupted or tampered with during downloading"

In a Browser on the Mac on which you want to install MacOS, use the link I provided above. The forum does not underline it because it does not have

httpS:

http://time.is

then use UNIX to set the UNIX date correctly, and the Mac time chip will be close.

A Mac from 2008 does not have Recovery in its ROM.

that typically means you need a DVD with an Installer on it from exactly these two choices:

1) a solid-color model-specific DVD that matches your model exactly.

2) a Full-Retail DVD such as the 10.6 Snow Leopard DVD with a picture of a Snow Leopard on a white background.

If you have an old drive, typically with 10.7.3 or later previously installed, you MIGHT be able to use that drive to start up your Mac from Recovery, even if the drive is not bootable.

If you have an old Backup drive from after 10.7.3, that is also said to have a Recovery partition, might be able to start your Mac in Recovery.

a Mac started from recovery has more options than one with no macOS at all.

Mac with ANY older version of MacOS has MANY more options.

¿So where are you starting from?

There is a way to acquire an Official Current El Captain ...sort of ...installer.

That version requires a WORKING MacOS /Applications folder into which your Working MacOS System can unpack and 'install' the "Install MacOS Install 10.11 ElCapitan..." Application.

Also, that download is a MacOS disk image file of an older variety.

what form is your macOS installer in now?

Do you have it on a USB stick" or on a completely different kind of device?

and is it ONLY the download, or the actual INSTALLER Image, which is a self-contained bootable version YOU built?

"Have been" over what timeframe? Those downloads have been updated, we do not believe they have stale certificates.

And at what point is this getting stuck?

on your linux system, is the date accurate to within five minutes or less to internet time?

http://time.is