Unknown server tag 'asp:ComboBox'(AjaxToolkit)

Question

HI I am using AjaxTookit version 3.5.40412.0 for developing web apps in VS2008. i am using combobox control in my page but once i run the apps it showing  Unknown server tag 'asp:ComboBox'  please help me how to resolve this issue. Regards Jeevan.

jeevan mummadi · Answer

Hi Sutish I uninstalled and installed new AjaxToolKit version 3.5.40412.0 And i created one new page with Ajax Combobox with ScriptManger and Updatepanel. Code : http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd > http://www.w3.org/1999/xhtml  > q c madhu kumar jani this time i am getting this error. Microsoft JScript runtime error: AjaxControlToolkit requires ASP.NET Ajax 4.0 scripts. Ensure the correct version of the scripts are referenced. If you are using an ASP.NET ScriptManager switch to the ToolkitScriptManager in AjaxControlToolkit.dll. why AjaxTookit version 3.5.40412.0 will not support Scriptmanager and updatepanel ? And i deleted scriptmanager and update panel from above code and added ToolKitScriptManger then i run the page. Now its working fine. But in real time i developed my asp pages are using script manger and updatepanel. give me solution? Regards Jeevan.

Suthish Nair · Answer

Its seems a TagPrefix error but in your case i think might due to AjaxControlToolKit. Remove all entries references reinstall download a new version install it and add it as reference and try. Before that create a simple another page and build a combo box if no probs exists try removing obout.

Ankit Nandekar · Answer

plz try with prefix cc1 instead of asp1 may be it will help u bcoz as sutish sir told that ur error is related to tagprifix.

jeevan mummadi · Answer

Hi All I added system.web.extension dll and ajaxtoolkit dll and i changed TagPrefix as asp to asp1 . Still i am getting same error  Unknown server tag 'asp:ComboBox' . this is my actual code please look into this. .style2 { height: 39px; } .TrReceiptHight { height:11px; font-size: 9px; font-family:Arial; } .ReceiptTableBorder { /* border:dashed 1px #000000 ; */ width:210px; } .TrBigFont { height:13px; font-size: 11px; font-family: Arial; } function printdiv(printpage) { var headstr =  ; var footstr =  ; var newstr = document.all.item(printpage).innerHTML; var oldstr = document.body.innerHTML; document.body.innerHTML = headstr + newstr + footstr; window.print(); document.body.innerHTML = oldstr; } Customer Entry --%> Customer Name AutoPostBack=True FolderStyle= > --%> > runat=server InitialValue= ErrorMessage=Please Enter CustomerName ValidationGroup=Validate> validationexpression=^[a-zA-Z\s]+$ Display=Dynamic errormessage=Please Enter Proper Name ValidationGroup=Validate /> Basic Charges (Rs) : 0 Customer Mobile Number AutoPostBack=True FolderStyle= > --%>   runat=server Display=Dynamic ErrorMessage=Please Enter Customer Mobile Number ValidationGroup=Validate> Display=Dynamic ErrorMessage=Please Enter Only Numbers ValidationExpression=^\d+$ ValidationGroup=Validate> --%> controltovalidate=txtmobileno validationexpression=^[0-9]{10}$ errormessage=Enter Valid Mobile Number ValidationGroup=Validate /> Font-Size=Small ForeColor=Blue> : ForeColor=Black Text=0> Drop Location AutoPostBack=True onselectedindexchanged=ddCabNo_SelectedIndexChanged> --%> FolderStyle= MaxLength=50> --%> onselectedindexchanged=oddlLocations_SelectedIndexChanged Width=180px Height=180px AutoPostBack=True> jeevan kumar kiran ErrorMessage=Select CabNo InitialValue=--Select CabNo-- Width=120> --%> ErrorMessage=Please Enter Drop Location InitialValue=--Select-- Width=186px Height=16px ValidationGroup=Validate>   Font-Size=Small ForeColor=Blue> : ForeColor=Black> Terminal runat=server AutoPostBack=True onselectedindexchanged=oddlTerminal_SelectedIndexChanged> runat=server Display=Dynamic InitialValue=--Select-- ErrorMessage=Please Select Terminal FolderStyle= ValidationGroup=Validate> ForeColor=Blue> : ForeColor=Black> Payment Mode ForeColor=Black oncheckedchanged=rbCash_CheckedChanged AutoPostBack=True /> ForeColor=Black oncheckedchanged=rdCard_CheckedChanged AutoPostBack=True /> ForeColor=Black oncheckedchanged=rbCorporate_CheckedChanged AutoPostBack=True /> Font-Bold=True>Total Charges (Rs) : ForeColor=Black Font-Bold=True>0 FolderStyle= runat=server OnClick=btnSubmit_Click ValidationGroup=Validate > OnClick=btnClear_Click CausesValidation=False> CausesValidation=False onclick=btnRefresh_Click> runat=server CssClass=ErrorText Font-Bold=True Font-Size=Small ForeColor=Blue> runat=server CssClass=ErrorText Font-Bold=True Font-Size=Small ForeColor=Blue> runat=server CssClass=ErrorText Font-Bold=True Font-Size=Small ForeColor=Blue> runat=server CssClass=ErrorText Font-Bold=True Font-Size=Small ForeColor=Blue>   Customer Details At Aiport --%> Cabs Inside Railway Station Serialize=true AutoGenerateColumns=false AllowGrouping=true FolderStyle=~/style/premiere_blue AllowSorting=true AllowFiltering=false AllowPaging=true AllowPageSizeSelection=false Width=100% PageSize=50 Height=300 > runat=server /> runat=server /> runat=server /> runat=server /> runat=server /> runat=server /> In this page i am using Obout controls( third party tools). Regards Jeevan.

Suthish Nair · Answer

Normally this error occurs when the TagPrefix does not match in source page you are using. try changing to TagPrefix=asp1 because asp is a reserved keyword in VS.Net. Might helps. I didn't see any error on this posted code might error occurred on some other page. Double click the error from error list window.

Ravishankar Singh · Answer

Can you check system.web.extension dll is refered in ur code or not? Also recheck the ajaxcontrol toolkit dll for combobox control by simply adding in Visual studio toolbox.

Ankit Nandekar · Answer

i Think there is a problem in ur ComboBox not in updatepanel or ScriptManager bcoz i dont have comboBox in my web controls it is in windows form .please check ur combobox is it in ur toolbox or not.

jeevan mummadi · Answer

Hi Ankit Untitled Page jeevan Kumar Arvind raj avinash dinesh i am giving only sample code to u. and i added more asp controls in update panel. Please tell me this version of Ajax toolkit controls are support scriptmanager and updatepanel. Because of i am using scriptmanager and updatepanel in every page. Regards Jeevan.

Ankit Nandekar · Answer

can i see ur code.