I had the same problem as Trent with some keys not working after upgrading to 220.127.116.11 so I tried to upgrade to 18.104.22.168 but have been unsuccessful. The OS is XP SP3 and the hosts are direct connect and running 22.214.171.124. The download completes, the installation starts, but ends without upgrading. The install window disappears after a fraction of a second and the text in it is garbled. Any help is appreciated.
I guess you recommendation will work. But when you completely remove the old version, you will lost the connection. So thay is why you wan to use Simple upgrade. But this dosn't work as well. Looks like it starts upgrading, but never finishes.
Please try using the Remote Install tool as a workaround and an alternative to Simple update. In this tool, the upgrade process uses a slightly different approach, so it should help override the problem with the restart manager. The update issue was fixed in the current version 126.96.36.199, but unfortunately, it will not work retrospectively. The new process will start to apply when updating Hosts version 188.8.131.52 (i.e. the now current version) and later.