--- In firebird-support@yahoogroups.com, "Paul R. Gardner" <gardnerp@...> wrote:

>
> I have a customer running Firebird 2.0.6. They run a Citrix environment
> and will have 200-300 simultaneous connections over a dozen or so
> databases.

Don't forget about 2GB address space limitation for 32-bit processes/

> Recently they upgraded their Citrix environment. Now there
> are times where they are unable to start a new instance of our program.
> When this happens, the Firebird.log file gets many error messages like:
> Database: ThreadData::start() failed:
> operating system directive _beginthreadex failed
> Not enough storage is available to process this command.
>
> I had them check the setting 'Allow service to interact with desktop' in
> the Firebird Server service properties. This was a solution I had found
> in the Firebird message boards. Unfortunately this did not solve the
> problem.

Make sure they restarted service after changing of serice properties.

> Has anyone run across this? Any ideas? I'm not 100% positive
> that the Citrix upgrade caused the issue either, it's just something
> worth mentioning.

Citrix could have different default size of desktop pool... It can be checked\tuned via registry.

Regards,
Vlad