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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
Use offline installer for Adobe Flash Player : Progress bar hangs during download / Unable to connect to server / Unable to download metafile
Download the Adobe Flash Player installer directly by right clicking the following link and selecting "Save target as".
Save the file to your downloads folder - DO NOT run anything yet.
Reboot your system.
BEFORE opening anything else, run the installer from your downloads folder.