Your wallet can become slow when you have lots of transactions stored in your wallet.
You can fix this by re-downloading the blockchain and and by performing a rescan.
Use the following instructions to fix your slow wallet.
Note 1: replace “DSFR” with the name of your coin.
Note 2: make a backup of the entire folder "%appdata%/DSFR".
1) Re-download the blockchain.
1.1) Stop your wallet.
1.2) Make a backup of the folder "%appdata%/DSFR".
1.3) Remove everything in the folder "%appdata%/DSFR" except wallet.dat.
1.4) Start your wallet.
Your wallet will download the complete blockchain, this might take a while.
2) Perform a rescan.
2.1) Stop your wallet.
2.2) Start your wallet with the parameter -rescan.
E.G. DSFR-qt.exe -rescan
2.3) Start your wallet.
Your wallet will check every transaction stored in your wallet, this might take a while.