MWS Error when trying to access B2B pages

Hi, would appreciate your help on this…

We have one of the external user connecting to our B2B Webmethods facing this problem from past few days. It was working fine for this user, until few weeks back!

Now, all their request are resulting in this error on our end :

2011-02-17 11:21:04 CST [ISS.0053.0002C] Access denied for user on port 443 -> ‘invoke/B2BDirect.Entry/processDocument’ from xxx.xxx.xxx.xx.

This shows that the User was able to reach until our Webmethods and even to the required package, but failed thereafter in authentication.

Can someone please help here, with your past experience…

It seems Extended settings (as mention above) is required even if defualt port(8585) is used for MWS ??