From the last message of the
http://tech.groups.yahoo.com/group/firebird-support/message/90460 thread:

"We have reinstall the Server at that time. It solved the Problem.
Im sure the Eset NOD32 causing the problem in my case.
Deinstall the AV was not enough to correct the problem."

Gabor

Gustavo írta:

> Thank you very much for your orientation. Evidently my problem is that of
> the limit of 63 TCP connections.
>
> I read everything you suggest and I learnt that apparently the problem can
> be solved by adding the HKLM key TcpNumConnections but I tried this and the
> problem continuos. This key wasn´t in the registry. So I added it and first
> I try with the default value ffffffe and it didn´t work. Then I changed the
> value to 999999 (decimal) and it didn´t work. I restarted Windows to be sure
> the new key was working, but the problem is still there.
>
> I also read that NOD32 antivirus may be causing the problem. This PC has
> this antivirus. So I deactivated it but the problem continuous.
>
> Perhaps I have to add any other key to the registry or I have to do
> something else.
>
> Does anybody have a suggestion?