Unable to connect remotely to my mailboxes server

Hello All,

Since couple of months, I'm unable to connect remotely (remote desktop) on one of my mailboxes server.

So here's the situation :

When I try to connect remotely on my server, it ask me my credentials. Once entered, the server drops the connection and than when I try back it is instannately dropping it. I don't get to the login screen.

Any clue?

Thanks

Johnny

Note : Windows Server 2008 R2 - Exchange Server 2010 RU4-v2