When trying to upload videos from my iPhoto app to Facebook, i get this error message, "Error validating access token. Session doesn't match current stored session" Anyone know how to fix this? Thank you.

iPhoto/Photos has changed to the central account management system vs settings stored in app, so if you go to System Preferences, select Internet Accounts, select Facebook, click Details and enter your login/password there (or delete the account and re-create if necessary) it should work. That fixed it for me.

yes! thank you...i reset my Facebook password (easy), logged back into Facebook, and had no problem sharing my iPhoto video to my Facebook timeline. thank you!