I had the same issue on an XP system with .NET 2.0, PowerShell 2.0 and PowerCLI 5.1 U2.
Confirmed also that installing .NET 3.5 resolves the problem.
I had the same issue on an XP system with .NET 2.0, PowerShell 2.0 and PowerCLI 5.1 U2.
Confirmed also that installing .NET 3.5 resolves the problem.