Geant4 B4example

Hello Rooters,
I am currently working on Geant4, and I’m running the example B4a smoothly.
As I want to see the histograms, I try to open the “plotHisto.C” with root, by opening root in the file directory and then executing “.x plotHisto.C” but I get the following errors. I have no idea what to do so any help is much appreciated! Thanks in advance!

Error in <TFile::TFile>: file B4.root does not exist

 *** Break *** segmentation violation



===========================================================
There was a crash.
This is the entire stack trace of all threads:
===========================================================
#0  0x00007fe1b399c687 in __GI___waitpid (pid=31631, stat_loc=stat_loc
entry=0x7ffec91457a8, options=options
entry=0) at ../sysdeps/unix/sysv/linux/waitpid.c:30
#1  0x00007fe1b3907067 in do_system (line=<optimized out>) at ../sysdeps/posix/system.c:149
#2  0x00007fe1b4595beb in TUnixSystem::StackTrace() () from /home/nick/Downloads/root/lib/libCore.so
#3  0x00007fe1b45985d4 in TUnixSystem::DispatchSignals(ESignals) () from /home/nick/Downloads/root/lib/libCore.so
#4  <signal handler called>
#5  0x00007fe1b4d3e47a in ?? ()
#6  0x00007ffec9148150 in ?? ()
#7  0x0000000000000018 in ?? ()
#8  0x00007ffec9148150 in ?? ()
#9  0x00007fe1b4d3e1d0 in ?? ()
#10 0x00007ffec9148160 in ?? ()
#11 0x00007fe1b4d3e32c in ?? ()
#12 0x000055ef83796bc8 in ?? ()
#13 0x00007fe1af0f3fb4 in cling::IncrementalExecutor::runStaticInitializersOnce(cling::Transaction const&) () from /home/nick/Downloads/root/lib/libCling.so
#14 0x00007fe1af08f05b in cling::Interpreter::executeTransaction(cling::Transaction&) () from /home/nick/Downloads/root/lib/libCling.so
#15 0x00007fe1af104553 in cling::IncrementalParser::commitTransaction(llvm::PointerIntPair<cling::Transaction*, 2u, cling::IncrementalParser::EParseResult, llvm::PointerLikeTypeTraits<cling::Transaction*>, llvm::PointerIntPairInfo<cling::Transaction*, 2u, llvm::PointerLikeTypeTraits<cling::Transaction*> > >&, bool) () from /home/nick/Downloads/root/lib/libCling.so
#16 0x00007fe1af104618 in cling::IncrementalParser::Compile(llvm::StringRef, cling::CompilationOptions const&) () from /home/nick/Downloads/root/lib/libCling.so
#17 0x00007fe1af08fd1e in cling::Interpreter::EvaluateInternal(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cling::CompilationOptions, cling::Value*, cling::Transaction**, unsigned long) () from /home/nick/Downloads/root/lib/libCling.so
#18 0x00007fe1af090657 in cling::Interpreter::process(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cling::Value*, cling::Transaction**, bool) () from /home/nick/Downloads/root/lib/libCling.so
#19 0x00007fe1af141a5f in cling::MetaProcessor::readInputFromFile(llvm::StringRef, cling::Value*, unsigned long, bool) () from /home/nick/Downloads/root/lib/libCling.so
#20 0x00007fe1aeffa0a4 in TCling::ProcessLine(char const*, TInterpreter::EErrorCode*) () from /home/nick/Downloads/root/lib/libCling.so
#21 0x00007fe1aefec227 in TCling::ProcessLineSynch(char const*, TInterpreter::EErrorCode*) () from /home/nick/Downloads/root/lib/libCling.so
#22 0x00007fe1b4444598 in TApplication::ExecuteFile(char const*, int*, bool) () from /home/nick/Downloads/root/lib/libCore.so
#23 0x00007fe1b4443d55 in TApplication::ProcessLine(char const*, bool, int*) () from /home/nick/Downloads/root/lib/libCore.so
#24 0x00007fe1b4925722 in TRint::ProcessLineNr(char const*, char const*, int*) () from /home/nick/Downloads/root/lib/libRint.so
#25 0x00007fe1b4925b14 in TRint::HandleTermInput() () from /home/nick/Downloads/root/lib/libRint.so
#26 0x00007fe1b45979c0 in TUnixSystem::CheckDescriptors() () from /home/nick/Downloads/root/lib/libCore.so
#27 0x00007fe1b4599358 in TUnixSystem::DispatchOneEvent(bool) () from /home/nick/Downloads/root/lib/libCore.so
#28 0x00007fe1b44aee01 in TSystem::Run() () from /home/nick/Downloads/root/lib/libCore.so
#29 0x00007fe1b444197f in TApplication::Run(bool) () from /home/nick/Downloads/root/lib/libCore.so
#30 0x00007fe1b49271f3 in TRint::Run(bool) () from /home/nick/Downloads/root/lib/libRint.so
#31 0x000055ef80daea6c in main ()
===========================================================


The lines below might hint at the cause of the crash.
You may get help by asking at the ROOT forum http://root.cern.ch/forum
Only if you are really convinced it is a bug in ROOT then please submit a
report at http://root.cern.ch/bugs Please post the ENTIRE stack trace
from above as an attachment in addition to anything else
that might help us fixing this issue.
===========================================================
#5  0x00007fe1b4d3e47a in ?? ()
#6  0x00007ffec9148150 in ?? ()
#7  0x0000000000000018 in ?? ()
#8  0x00007ffec9148150 in ?? ()
#9  0x00007fe1b4d3e1d0 in ?? ()
#10 0x00007ffec9148160 in ?? ()
#11 0x00007fe1b4d3e32c in ?? ()
#12 0x000055ef83796bc8 in ?? ()
#13 0x00007fe1af0f3fb4 in cling::IncrementalExecutor::runStaticInitializersOnce(cling::Transaction const&) () from /home/nick/Downloads/root/lib/libCling.so
#14 0x00007fe1af08f05b in cling::Interpreter::executeTransaction(cling::Transaction&) () from /home/nick/Downloads/root/lib/libCling.so
#15 0x00007fe1af104553 in cling::IncrementalParser::commitTransaction(llvm::PointerIntPair<cling::Transaction*, 2u, cling::IncrementalParser::EParseResult, llvm::PointerLikeTypeTraits<cling::Transaction*>, llvm::PointerIntPairInfo<cling::Transaction*, 2u, llvm::PointerLikeTypeTraits<cling::Transaction*> > >&, bool) () from /home/nick/Downloads/root/lib/libCling.so
#16 0x00007fe1af104618 in cling::IncrementalParser::Compile(llvm::StringRef, cling::CompilationOptions const&) () from /home/nick/Downloads/root/lib/libCling.so
#17 0x00007fe1af08fd1e in cling::Interpreter::EvaluateInternal(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cling::CompilationOptions, cling::Value*, cling::Transaction**, unsigned long) () from /home/nick/Downloads/root/lib/libCling.so
#18 0x00007fe1af090657 in cling::Interpreter::process(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cling::Value*, cling::Transaction**, bool) () from /home/nick/Downloads/root/lib/libCling.so
#19 0x00007fe1af141a5f in cling::MetaProcessor::readInputFromFile(llvm::StringRef, cling::Value*, unsigned long, bool) () from /home/nick/Downloads/root/lib/libCling.so
===========================================================

The root file the macro is trying to access does not exist.