I can't get absolutely *NO* answer from your server

Hello,

It's a while I'm experiencing a problem. Whatever the request I send from this
address of mine, I *NEVER* get back any answer from your server, nor from any
other www4mail's available.
I've tried to retrieve URLs, to get my weekly quota, to get the help file but
it looks like all these requests are simply ignored. 
I use the same syntax and mail software that I did when all used to be
working.

I talk to friends, some say they get response almost immediately, others say
they are in the same situation.

I think this has been dragging on for 1 month now, I'd be thankful to you for
any light you may shed. Why shouldn't your server work "specifically" on some
addresses? 

Thanks for your time and your help,
Elek