App store login problem - The data couldn’t be read because it isn’t in the correct format.

[Deepshade]

As of the end of Jan 2025 we have an issue with an older Mac (MacPro 2010, Sierra 10.12.6) running legacy software.

The backup software on this machine is requiring us to connect to the App Store to confirm my ownership of the app.

Which we suddenly cannot do
The store just puts up this message when logging in.

An unexpected error occurred while signing in.
The data couldn’t be read because it isn’t in the correct format.

Others in the Apple Community forum have the same issue.

has anyone manage to fix it (no, the Certificate/Keychain suggestion didn't fix it)

Help appreciated on this one.

 

[Adora]

Do you have activated iCloud advanced data protection on a device with a newer OS for the login address? You can't use it anymore on older versions for the AppStore too if activated.

 

[Deepshade]

Do you have activated iCloud advanced data protection on a device with a newer OS for the login address? You can't use it anymore on older versions for the AppStore too if activated.

No. But thanks for the suggestion. Must be something else

 

[Adora]

No. But thanks for the suggestion. Must be something else

Did you log in after launching the app prompted you to? Or did you log in manually before? If only the first, have you tried just logging in?

There were some major changes to the AppStore with High Sierra and later another one. It could be some things just don't work anymore.

Is there a reason you don't want to upgrade at least to High Sierra? I saw Mojave would also work, but I would prefer High Sierra in such a case.

 

[NoBoMac]

Is there a reason you don't want to upgrade at least to High Sierra?

First sentence of OP, I assume: running legacy software.

Under that assumption, could be on the app developer's side.

Quick scan of Apple's developer site points out that old method to verify app legally purchased was deprecated. New/current method needs to process a different format receipt for the app (receipts are stored in the app). And different hash coding of "license". And all done on server of app developer.

So, they might have abandoned validation of that version of the app, no longer have a server/out-of-business, etc, so App Store is getting a bad response back.

Or, it is a 9 yo OS last update 5+ years ago, internet/web standards have changed/moved on, so wouldn't be surprised that connection method from app to App Store might have been deprecated (eg. seeing weirdness on a Catalina box I have and Safari has been having issues connecting/displaying some websites, and that was last updated more recently than Sierra).

 

[Adora]

Mac Troubleshooting Summary

With over four thousand articles here about Macs and their problems, it can be tricky to know where to look first. Here’s a selection of starting points for troubleshooting and solving issues…

eclecticlight.co

You can also run EtreCheck. It's free if it hasn't to fix things for you. It shows you what might be wrong and it recommends posting the report online for others to help.

But it needs at least High Sierra and you have to download the older version from a non-official site like this maybe:

Download EtreCheck Pro for Mac

EtreCheck is a simple little app to display the important details of your system configuration and allow you to copy that information to the Clipboard. ...

mac.majorgeeks.com

Or the official site maybe offers you an older version if you open it with Sierra:

EtreCheck

www.etrecheck.com

 

[Adora]

First sentence of OP, I assume: running legacy software.

Oh sorry, I didn't see that somehow. Maybe the apps work with the self-signing command that is used for apps that stopped working lately, even with Gatekeeper turned off.

 

[Deepshade]

Did you log in after launching the app prompted you to? Or did you log in manually before? If only the first, have you tried just logging in?

There were some major changes to the AppStore with High Sierra and later another one. It could be some things just don't work anymore.

Is there a reason you don't want to upgrade at least to High Sierra? I saw Mojave would also work, but I would prefer High Sierra in such a case.

We have new Macs a the latest OS in the office. This one old Mac Pro Machine is still running Adobe CS6 and we often have jobs that need exchanging in the older Adobe Formats (still have designers out the who hate the Adobe subscription model and are still using CS6) - plus for archiving purposes so we can still open jobs (without paying a subscription... and yes we do have current Adobe subscriptions - but everyones hates the model and one day it will be dumped). So it's just makes sense to use this old Mac and archive all Adobe Indesign and illustrator jobs, no problems there.

The issue is the backup software that just refuses to launch (Intego Backup Express). FYI - we've been Mac users since the SE ;-)

 

[Adora]

We have new Macs a the latest OS in the office. This one old Mac Pro Machine is still running Adobe CS6 and we often have jobs that need exchanging in the older Adobe Formats (still have designers out the who hate the Adobe subscription model and are still using CS6) - plus for archiving purposes so we can still open jobs (without paying a subscription... and yes we do have current Adobe subscriptions - but everyones hates the model and one day it will be dumped). So it's just makes sense to use this old Mac and archive all Adobe Indesign and illustrator jobs, no problems there.

The issue is the backup software that just refuses to launch (Intego Backup Express). FYI - we've been Mac users since the SE ;-)

Okay, I see. The last version seems to be 1.4 from 2013 and was only available in the AppStore.

Is it even still available to download? Can you see it in your purchases list? I had a recent iOS app that got removed completely and I couldn't even use my installed version anymore.

If there was a non AppStore version it's always worth a try to ask for a free registration key. I already got one, because I missed it wasn't only in the AppStore.

Maybe they have such a version anyway, many developers do when you ask and tell you don't like AppStore apps or in this case, there is a problem. If it's the same version it can just be overwritten then maybe.

I once got a paid Mac app for free just by asking for a non app store version.

 

[Deepshade]

Okay, I see. The last version seems to be 1.4 from 2013 and was only available in the AppStore.

Is it even still available to download? Can you see it in your purchases list? I had a recent iOS app that got removed completely and I couldn't even use my installed version anymore.

If there was a non AppStore version it's always worth a try to ask for a free registration key. I already got one, because I missed it wasn't only in the AppStore.

Maybe they have such a version anyway, many developers do when you ask and tell you don't like AppStore apps or in this case, there is a problem. If it's the same version it can just be overwritten then maybe.

I once got a paid Mac app for free just by asking for a non app store version.

Int's no longer in the App Store. I've contacted Intego - awaiting response.

 

[Adora]

Int's no longer in the App Store. I've contacted Intego - awaiting response.

I hope they send you the same app without App Store dependency.

Sadly some just want to sell new versions or alternative apps if it doesn't exist anymore. I asked someone for a download link for the last version of 3.x of some app (where I have a license key for), that I don't have to download it from any dubious site. But they only wanted to sell me version 4.

Many old apps run on newer Macs. I still use 1Password 6 with Intel emulation on macOS 15.3. But they won't sell me a key for version 7, what would even run natively. They only have version 8 where you need a online account and a subscription.