I keep my apps updated, religiously. I use special software to monitor my apps and make sure that they are up-to-date and if they aren't, it notifies me so that I can update them (I could tell it to update them for me automatically but I prefer to manage the updates personally). Now, I understand Adobe's cooperation with Microsoft to allow Microsoft to provide the Adobe Flash player updates. I guess you figure that if the Flash player updates are a part of Windows Update, they will get applied regularly. But the problem is that when there is a new Flash update for IE, Microsoft doesn't always make it available promptly.....or, the update fails to install, as a "Windows Update" (for whatever reason). The point is, people can't always depend on Microsoft. Especially people like myself that want to keep their systems updated promptly. What Adobe needs to do is give people two options for getting their Adobe updates; one through Microsoft update and one direct from Adobe (instead of being told by Adobe's website, "All Adobe Flash Player updates are obtained through Microsoft Windows Update" or something to that effect. Right now, the information I have is that there is an Adobe Flash Player update for Microsoft IE that is version 18.104.22.1686 and that is not the version I have. I have an older, insecure, version. But Windows Update says that no updates are available. By not being able to download the latest version, manually, myself....direct from Adobe....this leaves my system more vulnerable. Now, how about you make the update available for download on your website!
If you are using Windows 8.x, you can download the update from the link at the bottom of the Flash Player issues on Windows 8 page. This will download the latest update from Microsoft (we don't host the Windows Update, just a link that downloads the update from Microsoft).
I don't have a similar link for Windows 10 if that is the OS you are using.
If the update is not showing in Windows Update it's possible that some other update needs to be applied first for it to display. For example, the https://support.microsoft.com/en-us/kb/3135782 (MS16-022: Security update for Adobe Flash Player: February 9, 2016) page states:
I'm not seeing a similar note for Windows 10, but it's a possibility that there is some security update required to be installed before a specific update will show as being available for installation in Windows Update.