>I already had this problem and this happened to me once again.
> 
>I have a table whose columns are showed as not existing, at designers (as at EMS SQL Studio or ErWin)
>and also at the DDL comands for the table. But if you execute a SELECT command on it, it list all
>existing columns, and their data.

What do the users typically do when this happens? Do you do any DDL against tables that are in use? Tell us a lot more about your situation, e.g. exact Firebird version (errors are more likely to happen on Fb 0.9.4 than Fb 2.1.5), whether you use UDFs or not (they're a common source of problems), operating system, is it used for anything besides Firebird, any particular type of antivirus etc.

The more specific you are in your problem description, the more likely you are to get good answers.

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