AdomdConnection permission problem

I am developing a Windows Form application. On one of the forms I display the results of a query to an Analysis Services database. I create the MDX command text by building a string.

Everything works, but users who do not have permission to access the database encounter and access error. I don't want to give all of the users permission to access the database. I want the application to use the credentials in the connection string. However, when I execute the AdomdCommand, it seems to be using the credentials of the logged on user instead of the "User ID" in the connection string.

How can I get the command to use the credentials in the connection string?

Dim cmdText As String = ""

Dim BdSalesBacklog As Decimal = 0

Dim oAdomdConnection As New AdomdConnection("Data Source=server;Catalog=PortalAnalytics;User ID=user;password=password")

Dim oAdomdCommand As AdomdCommand = New AdomdCommand()

Dim oAdomdReader As AdomdDataReader

Dim period As String = ddlPeriod.Items(0)

oAdomdCommand.CommandType = CommandType.Text

cmdText = "" & _

"SELECT " & _

"{ BNBTime.[" & period & "] } ON COLUMNS , " & _

"{ Measures.[Total Backlog Snapshot] } ON ROWS " & _

"FROM BNB "

oAdomdCommand.CommandText = cmdText

Try

oAdomdConnection.Open()

oAdomdCommand.Connection = oAdomdConnection

oAdomdReader = oAdomdCommand.ExecuteReader()

Catch ex As Exception

MessageBox.Show(Err.Description)

End Try

Do While oAdomdReader.Read()

BdSalesBacklog = oAdomdReader.GetDecimal(1)

Loop

oAdomdReader.Close()

oAdomdConnection.Close()

I called a developer friend of mine and he explained to me that SSAS requires the logged on user to have permissions in a Role in the AS database.

I created an AD group containing the users to whom I want to allow access, and I gave that group membership in a new AS Role. I assigned the role the permissions I wanted the users to have.

My application now works for all the users who need to run it.

Thanks