To view AppData, have a read of this: https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files
Or a faster way:
Press WIN-key + R to open the Run-command-windows.
Then enter either:
%APPDATA%\Bitcoin
or:
%APPDATA%
to open the AppData folder.
This does work WITHOUT activating to display hidden folders.
Then do what HCP said and look if the tree structure looks 'normal' (blocks folder exists, .. ).