NAS in explorer

Since a while I don't see my NAS in directory opus (as same as my other drives) - However I see the NAS in the multimedia devices and the networksturcture. Someone can help me with dthis?

What happens when you enter the NAS’s name or IP address in the location bar?

an error occurred reading the folder:
The networkname is no longer availeble (64).

I think this is something in the NAS settings and have nothing to do with Opus - I asked the same question in the synology forum. This topic can be closed. Thanx