Health monitoring is useful to administrators who need to monitor an application and be notified when a critical error occurs, or to developers who need to add instrumentation to a mis-behaving application.

Step 1 : Installing Web Event
You can do this easily in run-time mode with this code below:

Management.SqlServices.Install("Computer Name", "SQL user name",_
	"SQL password", "Database name", Management.SqlFeatures._
	SqlWebEventProvider)

Step 2 : Configuring Health Monitoring
Write these elements in web.config file:

<connectionStrings>
    <clear/>
    <add name="ConnectionString" connectionString="Data Source=(local);_
		Initial Catalog=DeveloperMeeting;
		UId=sa; Pwd=sa"/>
</connectionStrings>

  
<healthMonitoring enabled="true">
    <providers>
        <clear/>
        <add name="SqlWebEventProvider" 
        type="System.Web.Management.SqlWebEventProvider, System.Web, Version=2.0.0.0, Culture=neutral,
		PublicKeyToken=b03f5f7f11d50a3a" 
        connectionStringName="ConnectionString" maxEventDetailsLength="1073741823" buffer="false"/>
    </providers>
    <rules>
        <clear/>
        <add name="Application Lifetime Events Rule" eventName="All Events"
		provider="SqlWebEventProvider" profile="Critical" />
    </rules>
</healthMonitoring>

You must set health monitoring's provider. you have three selections.
1- SqlWebEventProvider
2- EventLogWebEventProvider
3- MailWebEventProvider

Item one uses SQL Server for storing events and item two uses windows event log.
I would like to use "SqlWebEventProvider" in this article.

Via rules you can tell to web event whether All Events or Failure Audits stores.

Step 3 : Getting events from data store
For this step we must write two simple stored procedures for getting data and cleaning data from data store.

CREATE PROCEDURE dbo.DM_WebEvent_GetLogEvent AS
    SELECT *
    FROM dbo.aspnet_WebEvent_Events
GO

CREATE PROCEDURE dbo.DM_WebEvent_ClearAllEvent AS
    DELETE 
    FROM dbo.aspnet_WebEvent_Events
GO

And two VB.NET classes for managing event log.(I used my SQL Data Provider VB.NET Class)