Problems with WMI data retrieval

Hi,

I am trying to get some data using WMI for some win2k machines.

I am unable to get the following data points:

1. MAC Address of a network adapter:
I am using table :-> Win32_NetworkAdapter and field :-> MACAddress.

The return value i am getting is : UNKNOWN, for all the machines.

2. List of installed Softwares :
I am using table :-> Win32_SoftwareFeature and fields -> ProductName, Version.

For this one, the error is strange. I am getting data sometimes and sometimes it throws an exception when I try to get the data (even though the WMI query executes without any error).

Let me know if anyone has any pointers for this one.

An early reply would be greatly appreciated !

Thanks in advance :-)

-- Kedar