[Galaxy S 4 Mini Q&A, Help & Troubleshooting] albaCross:
Hi,

Unfortunately I can't help you here, but I have a similar problem and it might be related to yours. I have also have a Samsung S4 mini GT-i9195 LTE. Originally with Android 4.4.2 but lately with no OS at all. And I can't figure out how to get one back. What happened, chronologically and (very) detailed:

I rooted my phone with KingoRoot, which worked fine as far as I can tell. When I didn't like the KingoSuperUser-App I installed SuperSU. But it failed to work, apparently because of Knox or something like that. I later wanted to flash my phone with a LineageOS ROM (lineage-14.1-20170505-nightly-serranoltexx-signed.zip) and therefore I wanted to install TWRP as custom recovery. As the usual way with Odin seemed a bit complicated to me at the time, I decided to install the "TWRP Manager" App, which went well. But as soon as I tried to install my ROM with it, it asked if my bootloader was unlocked. So, after searching the internet about that and it said that Samsung phones usually have an unlocked bootloader and only have to be rooted, I went on with installing the LineageOS ROM using the TWRP Manager. Mind you, I am not talking about the custom recovery that you have to boot in to by pressing Vol-Up+Home+On/Off-Button, I am talking about the app that you can download and just needs root permissions to do the same stuff. I had downloaded the ROM-zip onto my SDcard before and wanted to flash it from there.. Now, when I let the app go on, the screen just went blank. And this might be the moment I overreacted. I panicked and tried to start my phone again. But it only went as far as the Samsung logo and didn't go further and I had to pull the battery to turn it off. I then tried to boot into recovery mode by pressing Vol-up+home+On with no result, I then tried with Vol-down+home+On and found Download mode with:

ODIN MODE
PRODUCT NAME: GT-I9195
CURRENT BINARY: Custom
SYSTEM STATUS: Custom
KNOX KERNEL LOCK: 0x0
KNOX WARRANTY VOID: 0x1 -> this one might have been 0x0 the first time
CSB-CONFIG-LSB: 0x30
BOOTLOADER RP SWREV: 2
WRITE PROTECTION: Enable

After some research I downloaded Odin3 (v3.12.5) and managed to flash TWRP (2.6.3.0) onto my phone. And I found the ROM-zip file, but it would not let me unpack and flash it and it didn't help to uncheck the "Zip file signature verification." When I tried to flash I always got the same error massage:

Updating partition details...
Running boot script...

Finished running boot script.
Installing '/external_sd/lineage-14.
Checking for MD5 file...
Skipping MD5 check: no MD5 file foun
Warning: No file_contexts
Target: 1493971678
detected filesystem ext4 for /dev/bl
Can't install this package on top of
E: Error executing updater binary in
Error flashing zip '/external_sd/lin
Updating partition details...

And it gives a "failed" response. Now, I tried moving the zip to internal_sd and flashing with no better result. I also tried to flash a stock ROM which I downloaded from Sammobile.com. This didn't work either. The adb push method and the sideload didn't work out either.

Interestingly, when I go to "Reboot" -> "Power Off" to turn the phone off I get a dialog:

No OS installed! Are you sure you wish to power off?

-> "Swipe to power off"

-> then comes the next dialog:

Install SuperSU?

Your device does not appear to be rooted.

Install SuperSU now?

This will root your device.

-> "Swipe to install."

Which had no effect at all but to inform me that my phone apparently isn't rooted after all. I therefore downloaded the S4Mini_RootKit_v2.zip and tried flashing it, which was successful. But I still got the same dialog when powering off and I couldn't install the zip files either.

That's where I am now and I really don't know what to try or do next. As I could flash TWRP onto my phone, shouldn't it also be possible to flash an OS?

I hope this was a precise enough description. If someone has any further question, please ask.