Custom Timer job throws an error : "Value cannot be null. Parameter name: uriString"

Question

I am facing an issue while trying to write the custom Timer Job in SharePoint 2007.

Have overridden the Execute method

public override void Execute(Guid contentDbId)
    {
        using (SPSite oSPsite = new SPSite("http://esssharepoint20"))
        {
            oSPsite.AllowUnsafeUpdates = true;

            using (SPWeb oSPWeb = oSPsite.OpenWeb())
            {
                SPList splist = oSPWeb.Lists["PhoneBook"];

                SPListItem spItem = splist.Items.Add();

                spItem["PhoneNumber"] = DateTime.Now.ToString();

                spItem.SystemUpdate();

            }
            oSPsite.AllowUnsafeUpdates = false;
        }

    }

and registering the Job using a Feature

    public override void FeatureActivated(SPFeatureReceiverProperties properties)
    {
        //string oSPsiteURL = (properties.Feature.Parent as SPSite).Url;

        using (SPSite phoneBookSite = properties.Feature.Parent as SPSite)
        {
            SPWebApplication phoneBookApplication = phoneBookSite.WebApplication;
            SPJobDefinitionCollection timerJobCollection = phoneBookApplication.JobDefinitions;

            SPDailySchedule jobSchedule = new SPDailySchedule();

            jobSchedule.BeginHour = 0;
            jobSchedule.BeginMinute = 0;
            jobSchedule.BeginSecond = 0;

            jobSchedule.EndHour = 2;
            jobSchedule.EndMinute = 30;
            jobSchedule.EndSecond = 0;

           phoneBookPurgeData phoneBookTimerObj = new phoneBookPurgeData(
                "PhoneBook Timer Job",
                phoneBookApplication
                );

            phoneBookTimerObj.Schedule = jobSchedule;

            timerJobCollection.Add(phoneBookTimerObj);
            phoneBookApplication.Update();

        }
        //throw new Exception("The method or operation is not implemented.");
    }

however it throws the below error:

08/09/2011 22:29:30.60 Timer 7psa Critical The Execute method of job definition PhoneBookTimerJob.phoneBookPurgeData (ID 2519a803-af39-4a2a-ae42-8d177a609ed8) threw an exception. More information is included below. Value cannot be null. Parameter name: uriString

08/09/2011 22:29:30.60 OWSTIMER.EXE (0x097C) 0x0C7C Windows SharePoint Services Timer 72ae Unexpected Exception stack trace: at System.Uri..ctor(String uriString) at Microsoft.SharePoint.SPSite..ctor(String requestUrl) at PhoneBookTimerJob.phoneBookPurgeData.Execute(Guid contentDbId) at Microsoft.SharePoint.Administration.SPTimerJobInvoke.Invoke(TimerJobExecuteData& data, Int32& result)

Webapplication is still exists, what am I doing wrong? and how to fix this?

Answer 1

After fighting with the error created a new dll with the same code and it works like a champ.

Answer 2

Check that the site exist in PowerShell or in a console application

$site = Get-SPSite http://esssharepoint20

Just to be sure