make a wallet backup.
close the wallet.
make a shortcut of your
sin-qt.exe on the desktop.
right click on it and select properties.
Shortcut tab, in the Target field, add
-zapwallettxes (see photo below)
select some inputs
send to yourself, but NOT on the same wallet.dat. It can be an exchange wallet or running two SIN wallets on the same pc by changing the data directory and the port
send all funds as "subtract fee from amount".