What version of Windows 7 are you using? 32 or 64-bit?
If your using 64-bit, make sure you're not using the 64-bit version of IE as it does not currently support adobe flash.
To check the version of IE you're running, open an IE page, click on Help, then About Internet Explorer and make sure it doesn't say anything about 64-bit.
If it does, then you can access the 32-bit version by going to C:\Program Files (x86)\Internet Explorer, look for "iexplore.exe", right click and create a shortcut on your desktop or wherever,
now you have the 32-bit version of IE when you click that link and you should now be able to install the Adobe Flash player.
Hope this helps.