Hi Hadeel Jalamneh,
Like Pramod mentioned, this looks like a connectivity issue between the OutSystems server and the external SQL Server. In particular, I've seen this type of message in the past when the SQL Server instance was not configured to accept TCP/IP connections (and as such defaults to a Named Pipes connection type that is not supported by OutSystems).
If this is the case, then if you press the Test Connection button for the External Database Connection that you defined in Service Center it should also show an error. And the solution would be to enable TCP/IP connectivity in SQL Server directly.
Hope this helps!