Software update: FP4.SP28.B.065.20230420

My FP4 was updated through the 4G network to the latest update of FP, including patch of April 5th. My FP4 rebooted but then keeps on looping with the FP logo, and finally nothing happens.

I tried to re-apply the OTA update you mentioned but there’s an error message on FP4 screen:

Now send the package you want to apply to the device with "adb sideload <filename>"...
Supported API: 3
Finding update package ...
Verifying update package ...
Update package verification took 3.6s (result 0)
Installing update...
E: package is for source build SP25 but expecting SP28

Install from ADB completed with status 1.
Installation aborted.

I looked at some manifest files in the .ZIP file and found information related to this SP25. But not SP28.

Is this SP xx the versioning of the security patch?

I found this reference on lineage. Where the move from SP25 to SP28 is made.

At the end, I don’t know how to pursue with this OTA file.

My FP4 has the bootloader locked, and developer mode wasn’t enabled (my bad).

My only chance is to make this sideload work so that the FP4 can bootup normally, if possible.

Any hint is welcome.


That’s a reference to the build number:

The OTA update you downloaded expected the previous version (SP25), but your phone is already on the latest release.
The update did succeed but something went wrong and rendered your phone unbootable, which should have made it fall back to the previous version, which it didn’t.

I’m sorry, but you’ll have to #contactsupport, nothing we can do here :see_no_evil:

There have been several bricks reported for this update, someone should have a look at this! :roll_eyes:


Thank you very much for your quick reply. At least I know now that I can’t do anything myself to solve this. I’ll contact support as you adviced.
Again, a big thank you.

A post was merged into an existing topic: FP4 Root Access is possible, maybe a bit risky

I would count 2 so far, did I miss several others? I dont want to underestimate the risk and neither want to fear people too much.

Overall those 2 seem to be quite different, as here recovery is at least accessible, so what about a factory reset from recovery?

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Thanks for the hints.I’ll contact support.
My bootloader is locked, and no developer mode enabled.
I’m using the ADB sideload. At least this function works.

PS: I replied above to hirmsushi on his post where he dropped the OTA package, if you want more info on ADB sideload operation.

If I do a factory reset from recovery mode what will happen to my personal data?
Is there a way to backup my data at that stage and then reapply the backup data after the factory reset?

They will be lost and no I dont think there is a way to back.

All right, I know it’s very bad form to berate somebody who suffers, but backups need to be made before the disaster…
Unfortunately backups are among those annoying, apparently useless things people always tend to put off until later because “they are way too busy right now”… :slightly_frowning_face:

(That been said I’m sorry for your loss. I know today a lot of people tend to have everything on their phones, and losing it represents a major catastrophe.)


You are right factory reset is still an option, I was too quick to jump to a conclusion :see_no_evil:

Several bricks was probably a bit overstated, but the amount of update problems feels a bit high the last few days. I’d expect the phone to handle those more gracefully.


3 posts were split to a new topic: Best back-up method

I am an American, I have seen screen dimming on this phone. I think this issue is in fact due to adaptive brightness. I’ve seen similar issues related to HDR on windows PC. This is usually a bug. It’s annoying at best. I hope they patch this in a future update. In the meantime turn visual effects off or something to negate this effect.

Hi and welcome to the forum.
Are you resident in the US as well?

This topic, unlike most is authored by Fairphone and they will read your feed back but the issue is well discussed in a user topic.

Maybe this

Yes I’m a US resident. I think the issue is a bug with adaptive brightness on this form. The colors somehow change In the motion photos. There was a bug with HDR with unrelated hardware mentioned above. Where the image did not display correctly on windows 10 a while back. Yes this post was relevant to this topic. I was also here to talk about screen dimming issue. I still think it was relevant. It was most likely adaptive brightness bug. Thanks.

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