注意:可能是存在一些安全帐户问题，因为我们在未安装的情况下在开发环境中运行此代码，因此可以正常工作.

Note: may be there is some security account problem as we run this code in development environment without installing, then it works fine.

服务以哪种帐户类型运行?本地服务，网络服务，本地系统或用户.
尝试在本地系统"下运行它，并检查问题是否仍然存在?

Under which account type the service is running? Local Service, Network Service, Local System or User.
Try running it under Local System and check if the problem still persists?

我尝试了每个帐户，但均不起作用...所以我建议如果您有Project Server 2007，则只需粘贴我的服务中的代码，让您尝试一次.

实际上，在安装Win服务后，这两种东西无法通信.

I tried each account but it do not works ... so i suggest if you have project server 2007 then just paste my code in win service and let you try once.

Actually the two things cant communicate after installing win service.