looks like your network Admin needs to put some command on router .
dont see any problem in outlook .
This is just a restatement of the original question, which said that the problem wasn’t in Outlook, but probably a router command or network card setting. The right answer will tell me which command. I might add that the problem is not that the wireless network card temporarily loses connection to the router. Browsers continue to work just fine, as does incoming mail. It’s only the outgoing mail that stalls. Whatever could cause just that?
Check for port 25 or SMTP enabling settings on the wireless router. However, if it works sometimes and not others… then that makes this even more difficult to troubleshoot.