Umfpack64 can not work

after loading, while it can not work. and the character “defaulttoUMFPACK64()” can not be identified.

The word UMFPACK64 do not existe

use “UMFPACK64”

problem laplace(uh,vh,solver=“UMFPACK64”) = // Definion of the problem
int2d(Th,qft=qf7pT)( dx(uh)*dx(vh) + dy(uh)*dy(vh) ) // bilinear form

  • int2d(Th,qft=qf7pT)( f*vh ) // linear form
  • on(1,2,3,4,uh=g) ; // boundary condition form

Thanks for your advice.