Connecting to a windows network

I have a computer running QNX 2.5 on my windows network. I use windows services for Unix to connect to it from my windows computers. Works great, no problems for many years. I also have another QNX computer as a backup. It is supposed to be identical to the other QNX computer. I can ping it from any windows computer. I can see it from any windows computer that has services for Unix. But I can’t access it. I get the error message:

" is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions.

The network name cannot be found."

I know almost nothing about QNX. I have had the one QNX machine running for nearly 10 years. I have replaced all of the the windows computers on my network many, many times. All I ever have to do is install services for unix and then map the path.

Why can’t I do the same with the backup QNX computer? I looked at the passwd file, the group file and the exports file on both QNX computer and they are the same. What is stopping me from gaining access?