Check your Remote Access Setup control panel to see which ARA CCL script you are using. Sometimes if the modem you are connecting to does not support CNG signals, and you have selected the Express Modem 2.x/CNG in the Access Setup control panel, it will give you this type of error. Simply using the script Express Modem 2.x instead will let you connect.
So what is CNG
When you use the CNG scripts, the Express Modem will transmits data calling tones after dialing. Data calling tones allow the remote machine to detect automatically that an incoming call is a data modem instead of a FAX or Voice call, so the call can be routed to the appropriate software supporting the service.