Pictures missing in Photos App for Mac
Yesterday I updated my macbook pro.
After I everything was installed. I opened my macbook today I realised that almost all my photos from the Photo App on my Macbook had disappeared (years of photos). It wasn't even an update of the photo app but for Safari.... I could restore a few photo's from my recently deleted album. But those where only a hundred of the tens of thousands of memories/photo's I had.
I don't use iCloud and I don't have a time machine active
Where did they go? How do I get the years of photos back?
MacBook Pro (15-inch Mid 2012), OS X El Capitan (10.11.6)