I uninstalled McAfee and installed ESET Internet Security, but I got a problem that outlook mail could not be opened [memorandum until resolution]

I uninstalled the security software McAfee and installed ESET Internet Security, but a problem occurred where I could no longer open emails in Outlook.
In this article, we will explain the process that led to the resolution and also explain ESET.

Rakuten Mobile's base station was installed on the roof of the home apartment in front of Hiratsuka Station, but it is not connected at all!

A Rakuten Mobile base station was installed on the roof of my apartment in front of Hiratsuka Station, but unfortunately I can only connect to the Rakuten line near the window. It has been about a month since I switched to Rakuten Mobile with MNP, but I would like to report on the current status of base station maintenance and connection status.