Ok so i have seen so many people complain about this and rightfully so so i think it is time to give the fix that has worked for me and a few buddies of mine that had the same issue.
ok so a week or so ago i noticed i wasnt able to add or edit calandar entries andwhenever i tried viewing them the little bullet under the date would disapear...then it would come back. I did the same thing apple says to do which is to reinstall ios and so on which whats the point of having icloud if you have to deal with not having all your backed up stuff available to be restored....if i wanted to have a copy stored somewhere other than my phone i would just use my pc but i dont wanna lug around a heavy laptop or in my case an almost 4 grand machine when it was brand new so ya heres what i did:
1. you must have a jailbroken iphone....this is a perfect example why allowing more user access helps save time and money with support not to mention frustration on the part of the customer who usually gets told their phone is dead bring it in so a genius can tell u the same thing lol.
2. open ifile or load ifile if you dont have it already and open it.
3. go to var/mobile/library/calandar and delete everything listed. In my case there were 4 files. one was labeled extras and the rest were sqlitedb files. Just delete them. dont ask why cause if u do u obviously dont want this solved lol.
4. go into icloud and delete ur account and i selected dele the stuff off my phone since i already had it stored on icloud.
5. reboot ur iphone.
6. go back into settings and readd icloud and BOOM you calandars will be back up and running again. I never realized how many of my friends have birthdays this month too haha ya its been that long since i have seen my ical actually work. After hours of frustration at my phone getting ballz hot i decided to figure it out for myself cause no one elses solution was the right one for me and i appreciate the posts people made for sure but mine is for the person that cant disable their ical and when they try their phone stays on the spinning windows daying its being removed foreverrrrrrrrrr.
deleting the sqldb files removed all the ical info stored not the actual ical app. Once your resyncd to icloud ur phone auto pulls every single bit that was removed due to being corrupted back and sets it to function properly and so far im about 10 for 10 so i think its safe to say this can solve many peoples issue and i hope it does! spread the word guys.....now its time to go back to work. be safe and stay warm!