[nneonneo]

I have a fun one: my iPhone (12 Pro) refuses to acknowledge that it has eSIM functionality, even though the hardware exists.

I'm fairly sure I know what the problem is! It was restored from a backup taken on an iPhone X that had two physical SIM slots (Chinese version). The new phone now seems to think it has two physical SIM slots: it shows an IMEI2 in About, but any attempt to use the eSIM functionality just fails (scanning a code does "nothing"; no "add" button is visible, etc.).

If this was an Android phone, I'd root it and just fix the offending network configuration file. I believe it's possible to tamper with a backup of the phone to fix the issue, but this would mean a full backup+restore cycle and some specialized tooling to go mucking with the backup.

I filed a Radar on it ages ago, but I'm assuming nobody ever picked it up.

[praseodym]

Issues caused by restoring from backups were super common in the early iOS days. It makes me wonder how many weird bugs can be fixed these days by starting from scratch instead of migrating years of cruft through backup/restore.

[llacb47]

Quite a lot probably. I wasn’t able to use the health app on two different iPhones - it would crash after tapping “get started” consistently - and apple told me to just start from scratch instead of restoring from backup and there was no other way to fix it. Not a very satisfying answer

[rgovostes]

I had eSIMs get screwed up on my iPhone a year or two ago when I deleted an expired eSIM. It asked me "Do you want to update contacts to use <the SIM I just deleted>?" and I knew I was in trouble.

I did successfully use a backup editor, iMazing, to exclude the telephony data from a backup in order to fix it, but it cost me $30 and hours (transferring my Signal data to a second device and back). For 99.999% of their customers this would require a total erase-install. All because Apple has an off-by-one error somewhere.

[12_throw_away]

> I filed a Radar on it ages ago, but I'm assuming nobody ever picked it up.

I mean, based on all experience with Apple in the last 10 years, their bug trackers have presumably migrated to /dev/null for a backing db.

[ayewo]

You could try resetting only the Network Settings to see if that changes anything.

Settings -> Transfer or Reset Phone -> Reset -> Reset Network Settings