How to set up SQL server Agent? not showing in Sql Server Management

I am trying to set up the SQL Server Agent on our test server running with windows Small Business Server 2011 Standard and SQL Server 2008 R2 RTM. The Sql Server Agent node is not displayed in Sql management studio.

Here is what I know according to forums I read:

• in services.msc, I have two Sql Server Agent (Sharepoint and SBSMonitoring) set as automatic. If I try to start the service, the following warning comes up: The SQL Server Agent service on Local Computer started and then stopped. Some services stop automically if they are not in use by other services or programs
• in SQL Server Configuration Manager, under SQL Server Services, I have an error "The remote procedure call failed [0x800706be]". Under SQL Server Network Configuration (32bit), nothing is listed.
• in Local Security Policy, Security Settings -> Local Policies -> User Rights Assignement: their is no Sql Server Agent Listed
• in Sql Server Management Studio I created a new user with all the rights possible and after I logged with this user, Sql Server Agent was not showing
• I did the following command mofcomp c:\program files (x86) \Microsoft SQL Server\100\Shared\sqlmgmproviderxpsp2up.mof" but it did not change the error "The remote procedure call failed" in SQL Server Services

Does anyone have a solution according to these facts?

Thank you

select serverproperty('edition') returns Express edition. As confirmed you are using an Express edition. There is no way to get SQL Server Agent on this.