System.Web.Services.Protocols.SoapException: The permissions granted to user 'DOMAIN\username' are insufficient for performing this operation. ---> Microsoft.ReportingServices.Diagnostics.Utilities.Ac

I have a user trying to execute a report that uses ReportService2005:

They are getting this error and I can't figure out what needs to change to allow them access.

************** Exception Text **************
System.Web.Services.Protocols.SoapException: The permissions granted to user 'DOMAIN\username' are insufficient for performing this operation. ---> Microsoft.ReportingServices.Diagnostics.Utilities.AccessDeniedException: The permissions granted to user 'DOMAIN\username' are insufficient for performing this operation.
   at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall)
   at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
   at test.ReportService2005.ReportingService2005.GetReportParameters(String Report, String HistoryID, Boolean ForRendering, ParameterValue[] Values, DataSourceCredentials[] Credentials) in \\server\e$\Custom\ZZ\test\test\Web References\ReportService2005\Reference.cs:line 1289
   at test.frmMain.SSRSReport(String reportName, String company, String jobNum, String assemblySeq) in \\e101swtest\e$\Epicor\Custom\ZZ\test\test\frmMain.cs:line 337
   at test.frmMain.btnGo_Click(Object sender, EventArgs e) in \\server\e$\Custom\ZZ\test\test\frmMain.cs:line 203
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)