Can't open cells in hierarical schematic in Virtuoso

Hello all,

I have a design in Cadence Virtuoso (originally designed in SoC Encounter using NangateOpenCellLibrary 45nm std cells), when I try to open any std cell in the design schematic, I get these warnings and the std cell schematic open having all pins (inputs and outputs) marked as "unbound"

*WARNING* (DB-270337): Failed to open cellView (ipin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.
*WARNING* (DB-270337): Failed to open cellView (opin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.
*WARNING* Missing Masters:
Library Cell View 
NangateOpenCellLibrary ipin symbol 
NangateOpenCellLibrary opin symbol

and when I try to run LVS (between imported GDS layout and verilog netlist exported from Encounter), I get a bunch of these errors:


ERROR (OSSHNL-366): Instance 'I4' in cellview 'NangteOpenCellLibrary/AND2_X4/schematic' is bound to placed master 'NangateOpenCellLibrary/ipin/symbol'.
However, OSS has determined that it is not a valid placed master. Ensure that
cds.lib has entries for all the reference libraries and netlist again. Correct
this error and netlist again.

*WARNING* (DB-270337): Failed to open cellView (ipin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.

*WARNING* (DB-270337): Failed to open cellView (ipin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.
*WARNING* (DB-270337): Failed to open cellView (ipin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.
*WARNING* (DB-270337): Failed to open cellView (ipin symbol) from lib (NangateOpenCellLibrary) in 'r' mode because cellview does not exist.


Any suggestions ?