How to : Display Flash the right way in Ubuntu
Sometimes we would face a problem with displaying flash and video players based on flash while using Ubuntu. Most of times It’s because flash plugins were installed wrongly.
To Remove old plugins, We should Go to System > Administration > Synaptic Package Manager and type Flash in Quick Search form . You then would find some installed plugins (Checked Packages) .. All you have to do is to right click those checked packages and Mark them for Complete Removal .
After Removing them, It’s better to reboot your system, and then we can install flash plugin the right way :
sudo apt-get install flashplugin-nonfree
If It was Installed the same way like that, then you won’t need to do that .
You Would also like to check How to enable Flash in Chromium Browser By Rami Taibah .