PageRequestManagerServerErrorException: Value cannot be null

[Igor]

        function GetExternalData(userId) {
            var parameters = "GetExternalData," + userId;
            try {
                $find("<%= RadAjaxManager1.ClientID %>").ajaxRequest(parameters);
            } catch (e) {
 
            }
        }
	
When I call ajaxRequest method of RadAjaxManager I get a strange error:

'error': 'Sys.WebForms.PageRequestManagerServerErrorException: Sys.WebForms.PageRequestManagerServerErrorException: Value cannot be null. Parameter name: key'				

[msigman]

Hi Igor,

Try setting EnableAjax="false" on the RadAjaxManager for debugging.  This should allow you to see where the underlying error is happening.  Oftentimes the "Value cannot be null: Parameter name ____" is caused by a LINQ-to-SQL or LINQ-to-Entities call that has some bad data.  Specifically, it can happen when LINQ expects a field to be non-null, but the data coming from the database has a null value.  Let me know if that helps.

[Igor]

Thank you msigman, you are right. It was the bug in my code :)

[msigman]

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