After a downgrade back to Sierra, Photos won't open library. Help!!
Hi guys, I had to downgrade from High Sierra back to Sierra, as after I restarted my iMac, the latest update automatically installed, then wouldn't boot (tried everything SMC, cmd-r disk utilities, P-RAM, even safe mode...wouldn't boot etc ). So after a clean install, everything is fine apart from Apple Photos can't open the library as it's from a later version. What can I do? I could go back to High Sierra, but I'm not sure that's a good idea due to it messing up last time:/
Thanks
Chris
iMac, macOS Sierra (10.12)