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1) Launch Task Manager (Keyboard Shortcut : Ctrl+Shift+Esc)
2) Go to Processes Tab
3) Make sure you have clicked on "Show processes from all users"
4) Kill "iexplore.exe" process
Let me know if you have more queries.
I could not find iexplore.exe – I have explorer.exe—is that the same thing?
No, it's obviously not the same. You need to close all instances of iexplore.exe
Download the installer to your local disk, restart Windows, then run the installer before doing anything else.
You may follow Pat Willener's advise.
Also while installing Adobe Flash Player please make sure you have checked "Show processes from all users"
You may download offline installer for Adobe Flash Player from here : Flash Player for ActiveX (Internet Explorer)