Thanks for your answer but the problem is not to find missing pictures or folders.
The problem is to connect/synk the maps/pictures on the NAS with all the pictures I have gathered in different Collections in Lightroom.
I thought the procedure would be the same as when you connect lost pictures/maps (great link you sent btw) for that problem but if you have any idea how to solve this problem I would be so greatful
Let's back up. After you moved the photo files from the computer to the NAS, then what did you do?
And I don't understand why this link doesn't work for you, it explains exactly what you said you want, which is "to connect/synk the maps/pictures on the NAS with all the pictures I have gathered in different Collections in Lightroom"
So sorry, read the link carefully again and gave it another try and it worked so fine! Just my fault, not to experienced with this. You saved my day & month!!