Cannot install any APK file due to "Out of Space" misleading error (plenty of space)

I know there are tons of questions about this, but I have tried many possible solutions to no avail. I believe the "Out of space" error is misleading... I have a problem: **I cannot install any .apk file** no matter what I try... I can install apps using **Play Store** though. When I tap on an APK file in any file explorer, Android Package Installer launches. I tap the INSTALL button but I always got the following error: > Out of space {AnyAPKApp} couldn't be installed. Free up some space and > try again. I have *plenty* of space, but even a tiny 248 KB APK won't install with the same argument... This is the only problem I have with the ROM and it is very frustrating... First, the details of my case: - *Device:* Samsung Galaxy Grand Prime+ SM-G532M, alias Galaxy J2 Prime (Xtreme detects my device as *Model Number:* SM-G950F) - *Android:* 6.0.1 - *ROM:* Xtreme Ultimate V6.0 (15.07.2018) - *TWRP:* 3.0.2-0 - *Magisk:* v17.1 - *Magisk Manager:* 6.0.1 (151) - *Storage:* Adoptable - *Internal storage:* 7.02 GB used of 8.00 GB - *SD card:* 9.09 GB used of 14.70 GB - *Root Essentials "View storage used":* 9759/15787 MB (62%) - *DiskUsage analysis:* /system = 2.94 GiB; Free space 1.61 GiB I've already done my homework and tried all of the following to no avail: 1. Move all movable apps to SD 2. Enable Adoptable storage 3. Wipe *Dalvik / ART Cache* and *Cache* partitions with TWRP 4. Full clean with *SD Maid PRO* 5. Force move apps to SD using *SD Maid PRO* 6. Uninstall *Google Play Services* and *Google Play Store* updates 7. Overcome *unauthorized device* issue while using ADB 8. Trying to install APK using ADB (e.g. adb install someApp.apk). I got: Failure [INSTALL_FAILED_INSUFFICIENT_STORAGE] 9. Delete /data/log contents as suggested here 10. Attempt to install in Safe Mode 11. Using Termux and the df command, I got the following output and there is free space in each partition: df output" class="img-fluid rounded" style="max-width: 100%; height: auto; margin: 10px 0;" loading="lazy"> 12. Using pm install test.apk in a terminal emulator (*Termux*) I got [INSTALL_FAILED_INVALID_URI]. Using full path pm install /storage/emulated/0/Download/test.apk I got the same error: Failure [INSTALL_FAILED_INSUFFICIENT_STORAGE] The problem still remains. I think this is not really related to the full storage device error, I have plenty and the error seems misleading. It has to be something else... I gave as much info as I thought it was useful. If more is needed, just tell me to share it. I hope you can give me some advice to try to overcome this annoying issue. *P.S. I'll add more attempts to my list as I try them.*