It looks like that your catalog is corrupt. Do you have a backup from your catalog that you can restore?
It's for MACs but it's the same for Windows
Hi Axel I ended up phonong Adobe ant they got access to my laptop and reinstalled LR and seems everything is still there and now working although everytime I close LR I'm still getting the same error message I've had for weeks now saying media core.0 has stopped working... Any ideas about this?
Take a look here: https://forums.adobe.com/thread/1504823?start=0&tstart=0
Has Lightroom works in the past?
What has been changed before the error occurs, Windows updates, driver updates?
Try to restore your system to the date when LR still works.