Can't open networked file

[TimTDP]

I have 2 PC's that are connected wirelessly.
On the one PC, which I user as a server, I have shared a folder. I have also enabled "Allow network users to change my files"
On the second PC I have mapped a drive to the shared folder.
This works. I can see the shared folder.

In the shared folder are 2 files, named "Orders.mdb" & "copy of Orders.mdb" (Access 2000)

I can open both files on the server PC. No problem

However, I cannot open "Orders.mdb" from the second PC. If I user use Explorer to find the file and double click it, nothing happens. If I open Access and click file, open, navigate to the file, open I get a message that either the file has been opened exclusively by another user or I don't have permission to open the file. It is not being used by another user.

How do I set permissions to allow me to open the file?
Why can I open the copy and not the original?

I have even disabled the firewall!

Thanks in advance

 

[TimTDP]

I made a copy of Orders.mdb
Deleted Orders.mdb
Renamed the copy to Orders.mdb
It worked!