Cannot connect to the cube via pivot table control

[Hong Kong Is A Good Place]

I am using a pivot table control (OWC) via web access to an analysis server.

My connection string is:

ci.ConnectionString = "Provider=MSOLAP.2;User ID=peterdev01\\" + the_username +
";Password=" + the_password +
";Data Source=http://peterdev01/webtest;Initial Catalog=Peter ALL v2;Integrated Security=SSPI;Persist Security Info=True;Client Cache Size=25;Auto Synch Period=10000";

ci.DataMember = "PIER cubes"

I have set the above database security of analysis server to "All Users".

Then, on my pivot table control, it shows:
"The cube name 'Peter cubes' is invalid."

Why ?? How can I solve the problem?
Regards,
Peter