The library “Photos Library.photoslibrary” could not be recognized.

when I try to open the photos application the screen says "The library could not be opened." and underneath "The library “Photos Library.photoslibrary” could not be recognized."

It gives me two options, open other and quit, quitting quits photos and when i attempt to open other I have to create a new library. I would like to access the photos I had on before but cannot do so. is there any way to a) open the original photos library or b) access the lost photos?