problem in AMS simulation in virtuoso 5.1.4

[madihasheikh]

hi, I am new user of cadence incisive unified simulator. I want to run a mixed signal simulation. I am able to run a mixed signal simulation of a design consisting of a verilog module and an analog schematic module, when using cells only from analogLib in the schematic. The problem is when I use the cell from the foundry library there are errors in running the simulation. These are,

ncelab: *W,DLCILIB: Library name 'silcmos018' not found, defaulting to 'SILCMOS018'. Please see nchelp on this error.
ncelab: *W,CUNOUN: Cannot find any unit under SILCMOS018.pto:symbol in the design libraries.
ncelab: *E,CUCFUN: instance 'M1' of the unit 'pto' is unresolved in 'test_inv.inv_schem:schematic'.
ncelab: *W,DLCILIB: Library name 'silcmos018' not found, defaulting to 'SILCMOS018'. Please see nchelp on this error.
ncelab: *W,CUNOUN: Cannot find any unit under SILCMOS018.nto:symbol in the design libraries.
ncelab: *E,CUCFUN: instance 'M0' of the unit 'nto' is unresolved in 'test_inv.inv_schem:schematic'.
ncelab: Memory Usage - 14.6M program + 49.8M data = 64.4M total
ncelab: CPU Usage - 0.0s system + 0.0s user = 0.1s total (0.1s, 63.5% cpu)
Error encountered during NC elaboration for configuration test_inv.inv_schem_sim:config.

I have also seen nchelp for these errors, but I do not understand what it means and how to correct it.
Please help me for this problem