Only one instance of a scriptmanager can exist on a page
- by dotnetdev
Hi,
I design an ASP.NET web usercontrol and with a maskeditor and scriptmanager, I always get an object reference not set to an instance of an object exception at runtime.
Stacktrace is:
[InvalidOperationException: Only one instance of a ScriptManager can be added to the page.]
System.Web.UI.ScriptManager.OnInit(EventArgs e) +384613
System.Web.UI.Control.InitRecursive(Control namingContainer) +333
System.Web.UI.Control.InitRecursive(Control namingContainer) +210
System.Web.UI.Control.InitRecursive(Control namingContainer) +210
System.Web.UI.Control.InitRecursive(Control namingContainer) +210
System.Web.UI.Control.InitRecursive(Control namingContainer) +210
System.Web.UI.Control.InitRecursive(Control namingContainer) +210
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +378
What causes this?
Thanks