Error message: Error creating VM. Operation 'CreateVM CustomizationOp' failed. Error executing customization script.. Error message: Set-NetworkAdapter The network "Name of the NetworkAdapter" doesn't exist on the host. . Error Code: -1

Error message: Error creating VM. Operation 'CreateVM CustomizationOp' failed. Error executing customization script.. Error message: Set-NetworkAdapter The network "Name of the NetworkAdapter" doesn't exist on the host. . Error Code: -1

Root Cause:

The value for the Network may be incorporated with a wrong value. For example, you may provided Network Adapter which is not listed/available in VCenter.  

Resolution:

Navigate to 

WAP Admin Portal --> VConnect--> Connections--> Choose a Connection for the list--> Templates--> Choose a Template from the list --> Provide the appropriate value (available in VCenter) for the parameter 'NetworkName'