Mac Os Recovery won't work on my Mac Pro Made in 2007.

What do you mean they are too old to read anything, have you not tried to put your Snow Leopard Disk in your

onboard DVDs and boot using the C key. If you can get SL installed this way you would then need to update

SL to version 10.6.8, https://support.apple.com/kb/DL1399?viewlocale=en_US&locale=en_US and then check the

App Store to check for any further updates.

As your Mac Pro can only be upgraded as far a Mac OS X Lion you would need to purchase it from Apples Online Store

they then send you a redeem code that you use in the App Store. but you first need to have an operable OS installed on

your mac before you can do this.

There is no point recommending you a license to buy, as I said if your internal DVDs no longer work then you would need to replace at least one of them. you would need to search on line to see if you can locate an internal DVD drive that can definitely be used with a 2007 MacPro, ask in the MacPro community I gave you a link to, more specialist MacPro people there.

As you have shown you have the original DVDs and said you also have the Snow Leopard DVD, so there were would be no point in you buying further DVDs when you already have that covered.

One further question to clear something up is if you put Disk 1 of those grey Disks in to one or both of your internal drives and Restart while pressing and holding the C key, the keyboard you are using must be connected directly into the mac and not through a USB hub.

If you do find a suitable internal DVD drive and install it, you would then use the original grey Disk 1, when booted up to that disk you would then use Disk Utility to erase whatever is on the drive and then format it correctly.

Mac OS Extended (Journaled) on a GUID Partition Map. Then you can install the original OS the mac came with.

Then you should be able to install Snow Leopard from your SL disk. Then you would need to update that to SnowLeopard 10.6.8, do that from the link I gave you much earlier on. Check for any further updates in the App Store Updates section.

Having done all that then you may want to consider upgrading your mac to Mac OS X Lion 10.7.

To get this you would need to go to the Apple Online Store and purchase it as mentioned before it is about $20.

You then get a redemption code that you use in the App Store, to download it to your MacPro.

If you have your DVD player connected directly to your mac, insert the Snow Leopard DVD.

Restart your mac whilst pressing and holding down the C key until the mac starts to boot from the DVD.

Have you tried that.

Are you definitely pressing and holding the C key down while restarting your mac from the Snow Leopard DVD.

The crossed circle is an indication the mac is not finding a viable file system so can't boot, it does not sound like it

is attempting to boot from the DVD.

Do you know anyone with a working MacPro 2007 that you could get them to install Snow Leopard onto

a hard drive and then insert that hard drive back into your MacPro.

I have given you the list of compatible macs for El Capitan and it clearly states

A Mac Pro introduced in 2008 or later.

So therefore a 2007 MacPro cannot officially run El Capitan.

As I said before in an earlier post you can still buy Mac OS X Lion from Apples Online Store

it costs $20:00, you will be sent a code via e-mail that you then redeem through the App Store

but you will only be able to do this if you can get your Mac Pro up and running on Snow Leopard.

And you can only do that if you buy a new internal DVD drive for it, could be difficult to get.

Or if you know someone with the same Mac Pro and get them to install Snow Leopard on a drive from

your mac in their machine and then transfer it to yours.

When the 2007 MacPro was introduced it probably came with Mac OS X Tiger 10.4

the mac would have come with two grey DVDs. One install disk and one Hardware Test.

The next OS was Mac OS X Leopard 10.5, which only came on DVD,

next was Snow Leopard 10.6 only on DVD.

Next was Lion 10.7 and Mountain Lion 10.8

only available via download, and in very limited numbers on USB.

The OS's Mavericks, Yosemite and El Capitan were free and downloads only.

If you want to post a question on the Mac Pro community,

Mac Pro - Apple Community

Yes I know you have tried to boot from the grey Disk 1 on your internal DVD drives, but you say the DVD drives don't work.

So therefore you would need to replace other both or just one of those DVD drives.

Have a look at OWC, to see if they can help get a suitable internal DVD, I don't know what country you

are in so it is difficult to guide you to a mac parts seller.

You have also mentioned that you have tried the external DVD drive and that did not work either.

You have mentioned you have El Capitan on a bootable USB drive, I said on more than one occasion El Capitan cannot run

on a 2007 Mac Pro. You have also showed that when you do boot to the El Capitan USB it gives an error. I have given instructions on how to get over that error by changing the date in Terminal.

You have also said that you used to have El Capitan on this mac, which would either mean you had El Capitan installed on your 2007 MacPro by unofficial means which cannot be discussed here. Or the Mac Pro you have is not a 2007 model at all

but a 2008 or later model.

We are just going round in circles here. Have you posted a question in the MacPro community, I gave you link earlier.

But for now I am out of ideas.

If you click on the Mac Pro Community link, then look to the top right of the screen,

you need to be logged in to see the options, click on Post and then Discussion.

Give your post a title and then in your question outline exactly what model Mac Pro you have.

What your issue is, what you have done to try to rectify it and what Mac OS X install DVDs

you have, and the El Capitan USB, to see what others have to say about that.

As I said before El Capitan cannot be installed on a MacPro from 2007.

Why buy El Capitan, Apple provides it for free, always have.

How to upgrade to OS X El Capitan – Apple Support

The 'no packages were eligible for install' means the certificate for the installer has expired.

A raft of Mac OS X and macOS's certificates expired in October 2019.

A newly certified version of El Capitan was released by Apple and can be obtained from the link above.

If you want to try to install the El Capitan installer you have, boot to the USB installer.

When it is booted up, click on Utilities in the menubar and select Terminal.

Enter a new date, for example or just copy and paste

sudo date -u 011421002016

press Return

enter your password

press Return

If Terminal returns an error saying sudo : command not found, then try again without sudo.

Quit Terminal and select Install OS X from the Utilities panel.

Press Continue.

If this works then when the OS is installed and booted up you can Open System Preferences> Date & Time

and reset the time back to today.

But as I say if your Mac is definitely a MacPro from 2007 then it will not be able to install El Capitan.

Below are the basic mac requirements to upgrade to El Capitan.

Check compatibility

You can upgrade to OS X El Capitan from OS X Snow Leopard or later on any of the following Mac models. Your Mac also needs at least 2GB of memory and 8.8GB of available storage space.

MacBook introduced in 2009 or later, plus MacBook (13-inch, Aluminium, Late 2008)

MacBook Air introduced in late 2008 or later

MacBook Pro introduced in mid 2007 or later

Mac mini introduced in early 2009 or later

iMac introduced in mid 2007 or later

Mac Pro introduced in early 2008 or later

Xserve models introduced in early 2009

To find your Mac model, memory, storage space and macOS version, choose About This Mac from the Apple menu . If your Mac isn't compatible with OS X El Capitan, the installer will let you know.

There are however unofficial ways to get El Capitan on a 2007 MacPro, but they cannot be discussed here.

You will need to search the internet for advice and tutorials for that.