Ipad 2 IOS 9.3.5 - How to add a new root certificate to the trust store? Wikipedia inaccessible.

Sure. Go to https://letsencrypt.org/certs/isrgrootx1.pem in Safari on your iPad. It should prompt you to install the certificate.

There's no good way to do this, that far back.

Probably the least-bad option, which requires some work on a Mac with more recent software... Try creating a configuration profile with the LetsEncrypt root certificate and the LetsEncrypt intermediate certificate on a Mac with the Apple Configurator 2 app installed, and see if that configuration profile can then be installed on the iPad second-generation, and allow access.

Or use an alternate browser with its own certificate store.

Or replace the iPad 2 with something supported by recent or current iOS versions.

MacBook Air 13” mid 2011 (MacBookAir4,2) can be upgraded to High Sierra, and this certificate problem goes away.

Have a backup before the upgrade. https://support.apple.com/en-us/HT201250

Download the installer using Safari: https://apps.apple.com/us/app/macos-high-sierra/id1246284741?mt=12

Reboot the Mac into Safe Mode, attempt access to this site again, then reboot normally.

How to use safe mode on your Mac - Apple Support

What’s the history, here? If root certificates were somehow deleted (which wasn’t recommended in this thread), or were possibly mass-reloaded from another Mac running newer (and something wrong then happened) that can (potentially) cause access problems.

In addition to its usefulness for (for instance) loading the VPN settings for an affiliated organization’s VPN servers into the Apple devices of associated people, and for many other similar uses including loading organizational-associated certificates, manually loading a profile is how some sketchy apps hook more deeply into an iPhone or iPad, so, yes, it can be done.

Here’s how:

Trust manually installed certificate profiles in iOS and iPadOS - Apple Support

I don’t have iOS 9 around, so no way to test.

Backing up, resetting and reinstalling, and restoring might clear the Settings crash. Nobody here can know that.

Really? It looks like you can just go Settings/General/Profiles , select the certificate and choose "Delete Profile".

That is easy to fix. Go with Safari on you ipad to https://letsencrypt.org/certs/isrgrootx1.pem and follow prompts to install the certificate on you ipad.

You perhaps misunderstand (or I was unclear in) my reply - as directed to letters9numbers.

The method proposed by MrHoffman is reversible as you perhaps note. The method suggested later, by parapunter, is not readily reversible.

Fia-Lotta wrote:

How do i get that file into my Mac, the file is loading down, but how can i get it to the right place so it will help my computer?

This thread is about old versions of iOS for iPad and iPhone, so a different issue and different tools. For a Mac, your best option is to upgrade to Sierra or High Sierra or newer. If your Mac is permanently stuck at El Capitan, Open Keychain Access, select the System Roots keychain, and add and trust the newly-downloaded certificate. If you have access to a newer Mac (High Sierra or newer), export all of the certificates there, transfer, and import them.

Fia-Lotta wrote:

Thanks for your help, i can come to the system Roots, but after that Im bet ..... i just now try to load down Firefox, it might help!

What's the model and year of your Mac? Apple > About This Mac > (if the model and year doesn't show in that display) > select Hardware, and post the Mac Model Identifier from the Hardware Overview display. That Mac model identifier should be a string and a pair of comma-separated numbers, for instance, iMac21,1. Post that model identifier string here. With the Mac model and year, or the Mac hardware identifier, somebody here can fetch your upgrade options.

As for importing the certificate, that's akin to this:

Keychain Access > File > Import Items > select the certificate file that you've downloaded.

I don't have an El Capitan or older Mac handy to check that, though.

No that didn't function either have OS X 10.11.6 Firefox demand OS X 10.12

Mac Air 813 inch middle of 2011

Processor 1,7 GHz Intel Core i5

Memory 4 GB 1333 MHz DDR3

Graphichs Intel Graphics 3000 384 MB

You need utility called Keychain access. You can use Spotlight search to open it. Once in it, click on System padlock NOT the system roots in Keychains window. Also in Category window select all items. Open you download folder in Finder and grab the certificate you dowloaded(isrgrootx1.pem) and move(copy) it to Keychain access main window(has other certificates in it). Enter username and password as required by system. Double click on the certificate in Keychain access window. Expand trust menu. Select When using this certificate Always Trust. Password as required. And you are DONE.

I have an ipad 2. the most recent update for the ipad 2 is ios 9.3.5 (as stated above). The only thing i use this ipad2 for is as an ereader, checking out books from librarys, using the overdrive app.

(the problem , interestingly, i digress "Lets encrypt" which is part of Internet Security Research Group (ISRG), which is a non profit company,, has stopped supporting devices with this older ios with certificates,,lets encrypt supplies overdrive, a private company now owned by KKR, and evil hedge fund,,,,,,,,WTF,,,how many people using ipad2's are now throwing them away, and i am not in the mood to spend more $$$'s on another crapple machine, , pardon digression, i am currently having to read books on the macbook pro with adobe digital editions,,,overdrive does not support any mac os newer then mojave... double WTF )

So i am trying to figure out how to get this old Ipad 2, to work, so i can use it to borrow library books again with the overdrive app,,,i am an old ignorant troglodyte,,,so please make full explanation, and very simple,,,and i will still probably reply with many questions...

(i digress, i called kkr, i called overdrive,,,,of course no response )

so the problem for me, i think, is the same as the person who started this thread, how to add a new root certificate to the overdrive app so it will access the public librarys catalogues that i use to borrow ebooks.

the troglodyte