This is the error that almost all my WMI devices shows from time to time
Connection could not be established (800703E5: Overlapped I/O operation is in progress - Host: ##.#.#.#, User: me, Password: **, Domain: ntlmdomain:ME) (code: PE015)
The servers that I am currently monitoring are Win2008 x 86 servers with plenty of 4 Gb of RAM at least, checking at the very least 4 sensors: ping WMI CPU WMI RAM WMI service and on a couple of them, I am including WMI remote sessions.
Refreshing the probe, restarting the probe does not solve or do anything. Restarting the server, of course, solve the error for a couple of days.