Default Calender App Problem

[JohnnyNash]

Phone: IPhone 4 (3g), using version 5.0.1, Model (MC676LL)

I recently downloaded the update to version 5.0.1.
Once I did apparently it cause the calender app that came with the phone (The default calender, not one I have downloaded) to not work properly.
I can view the calender but all edit buttons are no longer there. The only buttons shown now are at the bottom and are as follows,
Today
List
Day
Month
I can go from month to month but cannot add any reminders or appointments because there is no edit buttons. Also when I turn the phone to show the list page I cannot add anything there.
Is there a place to reinstall this app? Is there a simple fix for this? Not sure how to correct it.
I can view appointments that were already in the phone before this happened.
Any help would be appreciated, Thanks
Johnny

 

[DaveM]

This can be solved by going into iCloud in Settings and turning on the Calendar. Then go back into the Calendar and see if your "+" button reappears. Once it's working you can turn the iCloud Calendar back off if you want and everything should be okay.

 

[JohnnyNash]

Thanks that fixed the problem.