how to set the conf file ,if my wallet is encrypted I'm working with bitcoin-qt to send payments, the config file is set to work with JSON-RPC.
it's include the rpcuser and rpcpassword, all calls I make to the wallet works fine, on the UI of the bitcoin-qt.exe I wanted to encrypt the wallet so every send payment I do from the UI will ask me for user password, I did it from setting->encrypt wallet. 
After that all calls from JSON RPC I get an error "The remote server returned an error: (500) Internal Server Error." . should I add something in the conf file ?
You need to issue the walletpassphrase RPC command to unlock the wallet for some time, before you can perform send operations.