>you true i did not exclusive, now my question is this, how many requirement is diffirent than single use.
>
>i thing firs exclusive on. i will do exclusive on in main prg?
>
>and other ???
>
> i boot my application from other pc,(close from first pc) it is working.
>thanks

I'm not sure I understand your question. First thing in multi-user envirnoment is

SET EXCLUSIVE OFF in the main program or
EXCLUSIVE = OFF in config.fpw

Then it's really good to have a framework, which can handle update conflicts. You need to use buffering (I prefer 5) for all your tables (or views or Cursor Adapters). You should have a good Error Handler. These are the basics of multi-users in few words. But you better do some reading on the subject in Help...