no mesh on domain

Hello,
i have a problem. i wanna compute my 3D object, but there is an error /warnings

warning:
No mesh on domains 1 3 5 7
in geometry 1, mesh case 0.
No mesh on domains 2 6
in geometry 1, mesh case 0.
No mesh on domain 4
in geometry 1, mesh case 0.
Not all domains are meshed.

Error:
Failed to find a solution.
System matrix is zero.
Returned solution is not converged.