Hi,
after viewing a TTree with the viewer, i added labels and marks, then i tried to save in my .root file with the command htemp->Write() written in the “Command” field of the tree viewer but i got this message:
htemp->Write()
Error in <TH1F::Write>: File mu0_1GeVtheta0.root is not writable
(Int_t)0
what i have to do to solve this problem?
Thanks