Automatic updates are turned off in my Firefox installation. Today, I updated v56.0 x32 to v61.0 x64 via a full download and install. Since I noted that the help|about menu wanted to update to v57, and v61 was available, I elected to do the full .exe download and install of v61 instead. I selected the install option to install the background updater feature (I forget what exactly it was called), figuring that it wouldn't be active as long as I had updates turned off in the general options. I chose to accept the default of having icons on the desktop, shortcuts, etc. Once the install was complete, I started v61 normally. A few minutes after the successful install, I received another firefox installer UAC blank screen request for permission to update, which I approved, since I figured there were last-minute updates to v61. The next time I started Firefox, I got version 57 per help|about, and a warning that it was out of date. Although this version is x64, it is running in "Program Files (x32)" while the v61 is running in "Program Files." The unexpected install of v57 down-leveled all my icons and shortcuts to point to the v57 version. If I hadn't had the benefit of multiple firewall warnings, and known how to interpret what I was seeing, this could have been quite unpleasant. As it is, an easy upgrade has now taken most of the afternoon. Apparently what happened is that the x32 version was not deleted and after the installer was active, it decided that the v56.0 version needed to be updated too. If I did not have my firewall running with program controls on Firefox per .exe location, it would have been much more difficult to realize what was going on. I'm still a little murky on how the second upgrade got kicked off, but I imagine it'll be clearer to someone who knows the internals. Suggested solutions: (1) When an x64 version is installed, the users should be prompted for disposition of the older x32 version. Deleting of the prior version is the normal action when updating, so there should be an option to treat the upgrade to x64 the same way. (2) Installer should not down-level shortcuts (in my case from v61 to v57), at least not without getting user permission. (3) ALL facilities should honor the update settings in the firefox options. Whatever did this update ignored the settings that I have verified in both versions to be set to "Never Check for Updates." Part of this was my fault; at first I thought that the x61 version had some last minute updates needed so I told clicked to allow. (4) Once an instance is started, Firefox always uses that version when a shortcut is used, even if the shortcut points to a different version. For example, if v61 is already running, and I click one of my shortcuts, a new v61 window is started. If nothing is running when I click the same shortcut, v57 starts. This behavior may cause additional confusion in an already murky situation. The shortcut should either start the version it points to or issue a message that it can't be started until the other version is quit. (5) It appears that the "Mozilla Maintenance Service" is installed under the program files x32 folder, and there is a maintenance service installer log from today. There is no maintenance service folder under program files, even though I think this is probably what I asked to have it installed. I don't see any warning in the v61 firefox install log that installation was bypassed. Again, it seems to me that such convolution is ripe for future issues, and the maintenance service should have been installed with v61, or at least a warning issued if that would be too complicated and it needed to be left in the program files x32 folder. I believe that implementation of these suggestions would help prevent a number of similar sounding problems I have seen reported. I do have three related questions: (a) The background silent update installer that is an option during the v61 install - what does it do and will it honor "Never Check for Updates?" If not, how do I disable it? (b) What does the Tools|Options|General option "Use background service to install updates" do? Does that need to be un-checked to disable silent updates, or will the "Never Check for Updates" option prevent its activation until I manually select an update? (c) How do I get rid of the v57 version without also loosing the installer service and without having to delete both versions and loose my config? If anyone is concerned about my use of the "Never Check for Updates" option please rest assured that I have years as a security professional and I have good reason for selecting this option. Appropriate controls are in place. Thanks for your help. It is appreciated. NOTE: The "Automatically Add" troubleshooting information failed and a back arrow erased all of my input above. Fortunately I saved a copy.