[RESOLVED] Confused by ResetPreferredList

I configured my AP wireless router as follows:
Authentication-mode : WEP
Authentication-type : Open System √Shared Key Both(I check Shared key)
And configured a KEY.

I use the example code in wzctool.cpp to connect wifi to AP.
I use DoConnect to connect to AP supply with correct KEY.
Then I use ResetPreferredList to clear Preferred list. and connect AP with a wrong
KEY. But the wince tool shows I connect to the AP successfully.
I'm confused. Can somebody unlock my mind?

gurus give below advices:
Your best references are MSDN and the "wzctool" sample from Platform Builder
wzctool.cpp in Platform Builder.

Sorry for my post, I don't check the return value of InterpretEncryptionKeyValue.