Can't connect to shared folder on the network because the "original item can't be found"

Apple HFS filesystem tracks files according to a (hopefully) unique identifier instead of a path when it can.

The fastest way forward is to forget the old location / clear the recent history / and navigate to the shared folder and reconnect.

If you can't clear up the history, please post a screen shot of where you are seeing the "old" mount point and perhaps we can guide you there once more detail is provided. In the absence of detail, this general procedure is offered in hopes it helps you resolve things.