Output problem

I am trying to open mhd files obtained from 3DSlicer on Paraviw which always gives me this output message:

warning: In unknown, line 0
warning: Populating font family aliases took 211 ms. Replace uses of missing font family "Courier" with one that exists to avoid this cost. 

and in layout I cannot see some mhd file that I could see some time ago.
What is the problem?

It seems you open this post twice. I close this one