Windows Calendar problems - HELP !

Every time I log on, I get Windows Problem Reporting dialog which reports
that Windows Calendar has stopped working. It then stops the program, files a
report and checks for the solution online.
I have checked the Startup programs, Startup Registry and Services which
start off at start-up. Windows Calendar (wincal.exe) isnt there at all !!
Can anyone help me out with this issue? I have no clue as to why Windows
Calendar needs to start in the first place !!
Its really annoying to see the problem reported at start up. Windows
Calendar works normally at other times.