Problems with hadd

Hi Experts,

I am trying to add some files using hadd. But I get the following messages :

hadd Target file: WZ_Herwig.root
hadd Source file 1: /work/asi010/OUCodeOutput/output/MC/WZ_Herwig/histo.root
Warning in TClass::TClass: no dictionary for class teeba is available
hadd Target path: WZ_Herwig.root:/
Error in TBufferFile::CheckByteCount: object of class TNamed read too few bytes: 18 instead of 105

I am using root version 5.34

Please help me to get rid of this problem. Thank you.