When I dial out I get to the username - password and thats all the further that I can get. I can't authenticate.

Your ISP may be requiring encrypted authentication. In this case, try changing the S58 register to 3 by adding the extra setting S58=3 in Dial-Up Networking for the TA's modem descriptor. A description of S58 follows:
S-register: S58
Usage: S58=n; S58?
Function: Client-side Authentication Protocol Negotiation
Unit: Decimal ASCII code
Range: n=1 PAP n=2 PAP between TA and PC; CHAP MD5 between TA and server n=3 ANY authentication protocol
Default: 1 (PAP)
Description: Sets the client-side authentication protocol to be negotiated during the Link Control Protocol (LCP) phase of PPP/MLPPP negotiation. Does not determine which authentication protocol is negotiated if the TA is used on the server side. S58=1 allows only PAP to be negotiated. S58=2 allows PAP between the TA and PC and CHAP MD5 between the TA and server. S58=3 allows any authentication
protocol. If the server does not allow PAP, set S58=2 to try CHAP MD5 with the server. If the server doesnít allow CHAP MD5 or the PC doesnít allow PAP, set S58=3 to allow any authentication protocol that the server requests. MultiLink connections are possible if the authentication protocol is PAP (S58=1 or S58=3), CHAP MD5 (S58=2 or S58=3), MSCHAP(S58=3) and possibly others (S58=3).