Unable to complete network request to host"localhost"

when i start my application it works fine,i have a datagrid with some
values if i traverse very quicly in these values(with some evnt on
datagrid value click) and application got hangs ,but if i work slowly it
never hangs.than if i again restart my application not machine,it shows
error(("Unable to complete network request to host "localhost") but if i
restart my machine it again works fine.


details of software i am using

version of the Firebird Server == firebird 1.5.3.4870
server


version of the provider == FirebirdNETProvider2.0

version of .net == Microsoft Visual Studio 2005


.Net framework version == 2.0


using Visual Studio


and below is the firebird.log details

WS1DT4 (Client) Tue Dec 05 17:23:01 2006
Guardian starting: C:\Program Files\Firebird\Firebird_1_5\bin\fbserver.exe


WS1DT4 (Server) Tue Dec 05 17:25:32 2006
INET/select_wait: select failed, errno = 0

WS1DT4 (Server) Tue Dec 05 17:25:32 2006
SRVR_multi_thread/RECEIVE: error on main_port, shutting down


when i start my application it works fine,i have a datagrid with some
values if i traverse very quicly in these values(with some evnt on
datagrid value click) and application got hangs ,but if i work slowly it
never hangs.than if i again restart my application not machine,it shows
error(("Unable to complete network request to host "localhost") but if i
restart my machine it again works fine.

the connection string i used is as below

User=SYSDBA;Password=masterkey;Database=C:\Documents and
Settings\User\Desktop\Wallet\Wallet\bin\Debug\MANAGE.FDB;DataSource=localhost;Port=3050;Dialect=3;Ch arset=NONE;Role=;Connection
lifetime=100;Connection timeout=100;Pooling=True;Packet Size=8192;Server
Type=0


if u need some specified information plz dont hesitate to ask ,i really
need to overcome from this error fast.


thanx

127.0.0.1?