OrCAD switch undefined error

I am trying to perform a cirucit simulation with a switch in the cirucit. The switch has been close for a long time before being opened at t = 0s.
When I run the simulation I get the following error:



**** INCLUDING SCHEMATIC1.net ****
* source PSPICE AGAIN
R_R1 N01660 N01684 15
R_R2 N01684 N02322 50
R_R3 N02122 N01704 3
R_R4 0 N01720 2
R_R5 N01720 N01704 60
R_R6 N01720 N01704 20
R_R7 0 N01684 50
V_V1 N01660 0 DC 80V
L_L1 N02122 0 .2H
X_U1 N02122 N02322 Sw_tOpen PARAMS: tOpen=0 ttran=1u Rclosed=0.01
+ Ropen=0ms

**** RESUMING "spice run again .cir" ****
.END

ERROR -- Subcircuit Sw_tOpen used by X_U1 is undefined


PLEASE HELP ME OUT!