Can't save on network -"You do not have permission"

Question

Hello,
I am having a problem saving on the network of our 4 computer network system in our office. All computers are Macs, and all are on our own private network. We have set up file sharing on all 4 computers, and we have set the "everyone" permissions to read and write. In addition, we have loaded all users on all computers and given all users read and write permission to the public folder on all computers.
The problem is this. We can access the files that are in the Public folder from all the computers. However, once we access the file from the host computer on another computer-the file comes over "read only". I have tried using Text Edit files and Microsoft Word files, and I am getting the same result. We are able to open the file and physically edit it, however the edited version can not be saved back in the Public folder. We get an error message telling us that we do not have permission to save the file in the folder.
We just created the network yesterday, and in addition we added a Time Capsule.

Answer 1

We have done that. The Public folders on all computers are set with "everyone" at read and write access. In addition, every user has been added with file permissions set at read and write access.
As an example, we backed up a Quickbooks file this morning to one of the computers Public files. When you put the file in on the host computer, the file under the "get info" tab is listed as read and write access for every single user. However, once you pull the file off of the public folder from another computer within our network, the file is listed as read only for every single user.
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