Error Opening CrystalReportViewer on the Webserver

When I try to open my CrystalReport on the Webserver I get this error;

Logon failed. Details: ADO Error Code: 0x Source: Microsoft OLE DB Provider for SQL Server Description: [DBNETLIB][ConnectionOpen (Connect()).]SQL Server does not exist or access denied. SQL State: 08001 Native Error: Error in File C:\Windows\TEMP\cryVls1a33 {982C3F01-7159-47A6-B65C-771961E1F48A}.rpt: Unable to connect: incorrect log on parameters.

I set the connection string in the report and if got the connection info correct;

        Dim ConnInfo As New ConnectionInfo

        With ConnInfo
            .ServerName = "##.###.##.#"
            .DatabaseName = "***"
            .UserID = "**********"
            .Password = "********"
        End With

Why does it work on my local host, but not on the Webserver?