I've a problem with JDBC Connection. In a thread I'm trying to connect a database (MS SQL Server 2000) in a infinite loop. Every time I open connection, do some data editing and close connection with Connection's close() method. But I think there is a bug in Windows. Even if i closed the connection, windows doesn't close the port and the connection gives "Address in use" error. I tried to use connectionPool to get connections. When their job is finished I closed them and give back to the pool. But there is still that "Address in use" problem. After a number of loop it gives this error. Can you help me Why this error happens and how can i fix it?