[WARN] Pluggable Transport process terminated with status code 256

In linux, Pluggable Transport process in recent versions of TBB get destroyed or terminated sometimes, since then I couldn’t use the obfs4 to connect to Tor network unless using the fresh TBB files, How can fix it without completely reinstall?

I believe this is probably due to AppArmor. Can you copy your /etc/apparmor.d/abstractions/tor file here? It should have something like,

  /usr/bin/obfsproxy PUx,
  /usr/bin/obfs4proxy Pix,