Can't connect to Oracle from webservice

[Tim Johnson]

I've built webservices that go at SQL Server before but now I'm in an Oracle
environment. If I try a simple Open command from a desktop app as a test it
works fine. If I try the same command from a webservice running under IIS on
that same desktop it fails.

Here's the logic I use:

string c = "Provider=OraOLEDB.Oracle.1;Persist Security Info=False;User
ID=xxx;Password=yyy;Data Source=ETLT";
OleDbConnection conn = new OleDbConnection(c);
conn.Open();

From a desktop app it works fine. If I debug into the webservice and Invoke
the method that tries this same logic I catch this error on the Open:

"Unspecified error: E_FAIL(0x80004005)"

Helpful, huh? I think this is some kind of Access Denied error code.

Is there some special configuration I need to do in IIS to make my
webservice be able to access Oracle? Maybe the "user" I'm acting as when
IIS/ASP.Net runs my asmx code is not allowed in?