System is a mixture of NW6.5 NW6.0SP5

I am having troublese with Windows 7. After installing Novell Client 2 (IR5) I can log onto the network successfully, with all drives mapping listed in the login script connectly properly. After that the login fail every time with the following error message:

LOGIN-LGNWNT32-890: The specified server is unknown.
LOGIN-LGNWNT32-430: The following drive mapping operation could not be completed.
The error code was 8884.

Can anyone help me please? Thanks