Help!! iPhoto will not open.

Remember we can not see you or your computer so you have to provide details

What upgrade did you do? What version of iPhoto do you have installed? Of the OS? what exactly happens when yo try to open iPhoto?

If you upgraded to Yosemite did you upgrade to iPhoto 9.6 from the App store? If you upgraded form iPhoto '08 (version 7.x.x) or earlier have you installed and RUN the iPhoto Library Upgrader?

LN

You can not use iphoto 9.6.1 unless you are using Yosemite OS X 10.10.x (10.10.2 is the current version)

And we need the exact error message

LN