TMVA Install in Ubuntu 20.04 LTS

I have installed root5 and TMVA4.2.0 and it is working perfectly.
I have installed latest root on ubuntu 20.04LTS, but I could not install TMVA.
It shows error about .rootmap.
Please guide me.
I also tried to install root5 on ubuntu 20.04LTS but again getting error.

Hi @Najimuddin_Khan ,
and welcome to the ROOT forum!
Please refer to Installing ROOT - ROOT for instructions regarding the latest ROOT release. Note, for example, that there is typically no need to compile ROOT from sources anymore.

If that does not help please let us know exactly what steps are required to reproduce your issue.