Checking service leaves messages in the log

[Niels]

Hi,

I'm monitoring the ftp service on a Windows machine. But this check fills the system eventlog with messages like

FTP Server could not create a client worker thread for user at host 127.0.0.1. The connection to this user is terminated. The data is the error.

I've tried both net.tcp.service and net.tcp.port, with no difference.

Is this supposed to happen?