i updated my mac but now it won't let me open iPhoto, are the photos gone forever?

You can open the iPhoto Library in Photos. Photos is installed by the system as a successor to iPhoto.

There are several ways to open the iPhoto Library. You can simply drag the crossed out iPhoto.app onto the Photos icon in the Dock. This wil open the last used iPhoto Library.

Or launch Photos while holding down the options key. Then select the iPhoto Library you want to open.

iPhoto is 32-Bit and sadly not supported by Catalina or later. If you open photos holding the alt/option key, you can select which library to open. Select your iPhoto library, then click open or press the enter key. Your iPhoto library is now in Photos.

Try reinstalling macOS because it sounds like the Photos app may be corrupt. Boot the Mac holding cmd and r keys for about 20 seconds. The Mac will take a little while to boot. Select ‘Reinstall macOS’ from the menu and go through the installer process

Hi - I tried this and it wont open. I am at wits end, so many precious photos I cannot access.

No data will be lost

I tried this and it wont open.

What happens when you try?