Microsoft NTAS version 3.1 sends an NBP Lookup reply that contains a an invalid number in the "enumerator" field (254 in our case), apparently the PowerTalk catalog manager is dropping this reply packet. However, the NTAS server will show up in the Chooser which seems to knows it's an invalid number, and sets it to 1.
The fix is to install the "Microsoft Windows NT 3.1 US Service Pack 2", available from the Microsoft Download Service (MSD). You can also call Microsoft concerning this collection of patches.
To locate Microsoft Corporation's address and phone number, use the vendor name as a search string. For technical and product support phone numbers, please refer to the Apple Tech Info Library article: "Microsoft Technical Support"
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