Re: Im trying to root my galaxy tab 3, BUT odin wont open.
1. Redownload Odin (from androidfilehost.com/?fid=23622183712465432 ), uninstall it, reboot and reinstall it.
2. Most versions of Android don't need Odin to root the ROM. What version are you running (and if it's 4.4.2, what's the kernel date - Settings/General/About device/Kernel)?