After a successful root, I tried to install twrp custom recovery, so I downloaded the appropriate tar file and flashed it using Odin, but the device never entered recovery mode when I attempted to, it only showed the Samsung logo and freezed there, but it could boot up normally to the system, so I tried the adb command "reboot recovery", it rebooted and freezed at the Samsung logo again but this time it also did the same whenever I tried to boot up the system, I am sure this can be fixed but I don't know how, Please help.
I have solved my own problem, I downloaded the s3 mini stock rom from sammobile.com and extracted recovey.img from it and tried to convert it to .tar format using some batch that I found on the internet then flashed it using Odin, but the problem persisted, so i decided to flash the whole rom accepting the fact that I will be losing all of my data and messages, for my surprise, the device booted and nothing were lost but the root, everything was intact, sms, contacts. apps and everything!
I think your issue is trying to flash
.tar instead of
.img. TAR is just archive format, that actually contains the image you need to flash.