Registry is the directory inside the windows operating system where windows stroes the configuration files about the operating system and sofwares which installed in your pc.Deleting or modifying the registory will cause crash of operating system.Registry editor stores the files in way of the binary digits 0's and 1's.
what is same icon problem? due to some crash of registory files,default programs of the all application were changed into one.
STEPS
1)open the run prompt by using clicking the windows and R key at the same time.And type cmd in that,it will
open the command prompt and type regedit
2) It will asks for the user account control permission click ok.your registry editor will open like this.
3) Then navigate to following path
hkey_current_user/software/microsoft/windows/currentversion/explorer/file exists/
In file exists folder you can able to see the lot of file extensions like .3gp,.api,.avi,.bin,.c,.cab at each extension
you can able to see "User chioce" option right click and delete it.Do this for all extension.
4) Then Restart your pc
