I've been trying to figure this out for the last few days. I just came on this job where they are using FileMaker pro, and they want me to develop a web-app to interface with it. I decided that using FX.php, in php would be pretty easy, and so I went about trying to enable Web Companion so that I can query the database. So, I'll open up a database, enable WebCompanion in Preferences -> Applications and then in File -> Sharing, and set the port to 591, which is filemaker's registered port. But here's the problem, I then port scan the filemaker server, to see if 591 is open, it's not. Then I'll close the datbase, reopen it, and then WebCompanion in File->Sharing is diabled. Does anyone know what's going on?

Using FileMaker Pro 5.5 to interface with FileMaker Server 5.5.

If your db is shared by a filemaker server you must close the db on the server, open it in a Filemaker Pro client, enable web companion sharing, & then re-open it on the Filemaker Server. Once you do this the sharing settings will remain.

Your port scan should not be to the Filemaker Server, but to the Filemaker Pro client that has the database open. The client is the computer that actually has the db open and the web companion enable. The Filemaker Pro client is also the computer that your web clients will contact.

Now wait a minute. You're telling me that the Web Companion can only be served to the internet by a client with the database open? isn't that like having a server for Filemaker pro and then another machine to serve the Web Companion? So the File Maker Server has no functionallity to serve Web Companion stuff, that has to be done through a client that, I might add, has to stay on and leave the filemaker database open. Does anyone else see a problem with this?

I see no problem with that. You do not need server for serving web with Unlimited. You will need server, if more than 5-10 machines are using the same data. Up to 5 clients it is OK to use just client as server.