I imagine the IP address of any connected devices will have changed. These are assigned by the router automatically, by default. If you've changed your router, then the IP addresses will have been reassigned and may be different.
The file may show up in your favourite hosts list, as this is a list of shortcuts.
I'd recommend you clear your favourite hosts and files and reopen the file by browsing for it (Open Remote...) and looking in local hosts.
Yes what you say is a consideration, however, as i said, each machine once switched over physically by changing the cables, has been reallocated a new Ip ( by DHCP from the router) and it was checked. Hence the machines are able to print and share files. ( I agree if the old IP was retained they could also do that) but it was checked form the "ipconfig /all " command line that the machines were now on the new router network (esseentially changed from 192.168.0.1 255.255.255.0 to 192.168.1.1 with sub net mask of 255.255.255.0.
Thanks for the input anyway. ANy other ideas - it is strange.
NB. The hosts file for Filemaker was removed and reset, but is there a cache that needs to be cleared??
silly thought but have you tried moving the database to the other machine (Machine 2) and see if Machine 1 can see it ?
Yes KAPS. This is what makes if frustrating as to where is issue could be. If DB is hosted on Machine 2, fine Machine 1 can open remote and share. If machine 2 opens a FMDB that is on Machine1m it can be shared back to Machine 1. Just Machine 1 cannot share its own FM DB over the network