Proteus 8 component package error message
The error messages seem quite straightforward. They say that when you added those connectors J1, J2, and J3, you specified (or left as a default?) a package type "MOL_xx_ST that is not found in the software library of Proteus 8.

You can fix this by either:


Changing the package type to something that is in your library
Adding the "MOL_xx_ST" packages to your library.  ("xx" is the number of pins)