Restart / Shutdown problem

When I sometimes need to restart my P.C. I use Start then the option
restart, the P.C then shutsdown but will only restart manually, what is
happening here.

 

What operating system?

 

Windows Shutdown Problems
http://www.aumha.org/a/shutdown.htm

Or search MS Knowledge Base
http://support.microsoft.com/default.aspx

Or use MS Google search
http://www.google.com/microsoft.html

http://dts-l.org/goodpost.htm

HTH