The NPM installation prompts you for a port, default is port 80, which is used for the NPM web console access.
Verify the Windows server IIS web service is running:
1) Open CMD prompt
2) execute the following command: services.msc
3) scroll down dialogue box list to "World Wide Web Publishing Service" and verify status of "running"
Here is as example to access NPM using the default installation: http://192.168.201.151
NOTE: If during installation the default port was changed, the URL will need to have the port set after the IP address.
Forgot to mention.... After NCM initial installation is done the configuration wizard executes and this is how the NCM "Web Console" can be installed. If the Web-Console is configured via the wizard the default HTTP port is 8888.