Can someone help...I am using LR CC and I recently had some updates. When I reopen lightroom all of the folders in my catalog had the dreaded ? next to them....I have tried to re-add them to the current catalog but LR says they already exist. WHERE? I have so many jobs going now and I really need to find the folders with all of my current edits and flag selections. I use a iMac with OS X Yosemite version 10.10.3
Most likely, Lightroom thinks the photos are in the folers with the question marks, and so you have to right-click on the folder and select Find Missing Folder to fix this problem.
Re-importing photos never fixes anything and usually makes things worse.
Sounds like something/someone moved the folders, so that LR no longer knows where they are.
You just need to use the Folders panel in LR to relocate the "missing" folders.