What kind of license did you get with your copy of Filemaker Pro? (Not asking about server here.)
The error message you describe is intended to pop up if two or more filemaker clients connect to the same database and either both are single user licensed with the same license number or all the clients are volume licensed and you have more copies linking to the database than the maximum number of "seats" specified for this license.
Thanks for trying to help. I had a FM Pro Adv single user license (on Mac), accessing FM server (on Win 08 server), which hosts both "A" and "B" databases. I open only "B" database, and it must access "A" data through External Data Sources. Working on "B" database, in "manage database->relationships", when i try to add a table from "A"database the message appears. I've tried to add this external data source using his internet IP (189...), his LAN ip (192...) and 127.0.0.1, and anyone worked.
I've tried to add this external data source using his internet IP (189...), his LAN ip (192...) and 127.0.0.1, and anyone worked.
What does "anyone worked" mean? The IP you use isn't the issue here as far as I can tell...
Were there other users accessing this database at the same time? Is there any chance that any of these users also have a copy of Filemaker advanced with the same user license? (this is the first option we have to eliminate before looking at other possibilities...)