Be advised that following the instructions below will COMPLETELY remove your BitsharesX wallets!!
Proceed with caution and backup your wallet and the directory below if you have funds in your wallet.
In addition to uninstalling in Windows, which you seemed to have done already, you will have to remove the whole Bitshares folder in:
c:\users\username\AppData\Roaming\Bitshares X
where username is your username.
You can then re-install.