Question

错误类型“CrystalDecisions.CrystalReports.Engine.ReportDocument”同时存在于“c:\WINDOWS\assembl

错误 1 类型“CrystalDecisions.CrystalReports.Engine.ReportDocument”同时存在于“c:\WINDOWS\assembly\GAC_MSIL\CrystalDecisions.CrystalReports.Engine\10.5.3700.0__692fbea5521e1304\CrystalDecisions.CrystalReports.Engine.dll”和“c:\WINDOWS\assembly\GAC_MSIL\CrystalDecisions.CrystalReports.Engine\10.2.3600.0__692fbea5521e1304\CrystalDecisions.CrystalReports.Engine.dll”中 D:\WebSite3\Default.aspx.cs 19 5 D:\WebSite3\
下面是我的代码，用水晶报表连接oracle数据库，显示一个表，引用已经添加好。请问是哪里的问题？
using System.Data.OracleClient;
using CrystalDecisions.Shared;
using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Web;

ReportDocument rdoc = new ReportDocument();
string strsql = "select * from GT_STATIONDOC";
OracleConnection conn = "Data Source=orcl_192.168.31.1;User ID=tsgljl;Password=6075776;Unicode=True";
conn.Open();
using (OracleDataAdapter sda = new OracleDataAdapter(strsql, conn))
{
DataSet1 ds = new DataSet1();
sda.Fill(ds, "GT_STATIONDOC");
rdoc.SetDataSource(ds);
this.CrystalReportViewer1.ReportSource = rdoc;
}
我用的VS2008，建了一个DataSet，建了CrystalReport.rpt,在视图中添加了一个CrystalReportViewer，和ReportSource，没有其他了

Answer 1

说明: 在编译向该请求提供服务所需资源的过程中出现错误。请检查下列特定错误详细信息并适当地修改源代码。

编译器错误信息: CS0433: 类型“ASP.footer_ascx”同时存在于“c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\gzbm\8e6e88d9\c3f915a2\App_Web_-ibiwax6.dll”和“c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\gzbm\8e6e88d9\c3f915a2\App_Web_footer.ascx.cdcab7d2.wsgz59pf.dll”中

源错误:

行 301: <div style="DISPLAY:inline;MARGIN-LEFT:6px">

行 302: <div style="WIDTH: 100px" align="center">
行 303: <uc1:footer id="Footer1" runat="server"></uc1:footer></div>
行 304: </div>
行 305: <script language="javascript">

各位大虾应该怎么样去解决这个问题啊，详细解决步骤要给出来啊
不懂呀