我做的网上公告系统，调试出现以下错误，我找不到错在哪了，

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: [Microsoft][SQLServer 2000 Driver for JDBC][SQLServer]对象名 'Placard' 无效。
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:848)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:781)
org.apache.jsp.placard.placardlist_jsp._jspService(org.apache.jsp.placard.placardlist_jsp:179)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

root cause

java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC][SQLServer]对象名 'Placard' 无效。
com.microsoft.jdbc.base.BaseExceptions.createException(Unknown Source)
com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
com.microsoft.jdbc.sqlserver.tds.TDSRequest.processErrorToken(Unknown Source)
com.microsoft.jdbc.sqlserver.tds.TDSRequest.processReplyToken(Unknown Source)
com.microsoft.jdbc.sqlserver.tds.TDSExecuteRequest.processReplyToken(Unknown Source)
com.microsoft.jdbc.sqlserver.tds.TDSRequest.processReply(Unknown Source)
com.microsoft.jdbc.sqlserver.SQLServerImplStatement.getNextResultType(Unknown Source)
com.microsoft.jdbc.base.BaseStatement.commonTransitionToState(Unknown Source)
com.microsoft.jdbc.base.BaseStatement.postImplExecute(Unknown Source)
com.microsoft.jdbc.base.BasePreparedStatement.postImplExecute(Unknown Source)
com.microsoft.jdbc.base.BaseStatement.commonExecute(Unknown Source)
com.microsoft.jdbc.base.BaseStatement.executeQueryInternal(Unknown Source)
com.microsoft.jdbc.base.BasePreparedStatement.executeQuery(Unknown Source)
eshop.bean.PlacardDao.getCount(PlacardDao.java:191)
eshop.bean.PlacardDao.getPagedPlacard(PlacardDao.java:137)
org.apache.jsp.placard.placardlist_jsp._jspService(org.apache.jsp.placard.placardlist_jsp:49)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.9 logs.