Server not available on GroupShare

Hallo everybody

My name is Valeria

Can somebody please tell me why sometimes some servers on GroupShare are available and sometimes not? Last week it worked perfectly, and now the same server is unavailable.

I receive an error message like "Communication o connection errore". I've already checked the server settings and the're OK, so my personal credentials (they are right). How can fix this problem? It depends on me or on my customers??

Thank you very much

Valeria