WebKit.dll not designed for Windows

I'm running Windows 7 Ultimate 64-bit. Adobe Air file version 19.0.0.241. Whenever I try to run an application, I get the error message

When I try to correct the problem by re-running the Adobe Air Installer it tells me "This version of Adobe Air is already installed on your computer." When I try to uninstall Adobe Air so I can reinstall it, nothing happens. I'm the owner/administrator of the computer, so no help there. I've found the log. I don't see any entries that look helpful, so I haven't inserted the log yet, but will if it would help. I haven't yet tried uninstalling while running in Safe Mode. I have run the installer from an elevated command prompt but get no different results, including with uninstalling. I only run one AIR application, a desktop widget from Accuweather; I can live with not being able to run it, but would like to have it if I can.