Hello Gridsters,
For those who are aware of the trick but your wallet is still not auto-unlocking to stake, you may skip reading and scroll straight down to the fix/solution.
I believe we "Gridcoin stakers" most times forget to unlock our wallets to stake the coins in them most especially when windows auto-start our wallet after login in. Another major reason we forget is the time it takes the wallet to load the blocks and verify the database on start-up. We most times get carried away doing other things while its loading.
I have been wondering and searching for ways to automatically unlock the wallet just for staking purpose without success until I came across a beautiful write up written by 
IMPORTANT
Before we go ahead, let me emphasis the importance of "encrypting" your wallet. It is an additional layer of security but by so doing, one will have to manually click on the unlock button/icon (GUI - windows) on the lower left bottom of the wallet to unlock the wallet in order to stake or authorize coin transfer.
AUTOMATION
To make the wallet to automatically unlock itself "only for staking", you will have to insert some codes in your "gridcoinsearch.config" file which will be generated using the wallet's console/terminal.
1 - Go to Menu -> Help -> Debug -> then click on the "Console" tab.
2 - Type in execute encrypt YourPassPhrase.
3 - Your encrypted passPhrase.
Here is the fix/solution,
Make sure it the first line of code at the topmost. If you place it anywhere else, your wallet will not auto-unlock for staking
4 - Type in the string in your gridcoinresearch.conf as autounlock=YourEncryptedPhrase
Like he rightly said, this will only make your wallet to be able to stake. It will not fully unlock your wallet for coin transfer or do any other coin debiting action/commands like voting or beacon advertising. Also note that, the encrypted password string generated is unique to the current computer configuration and will not work if you move your configuration file to another system.
Thank you for your time and good luck
The post by
Additional link http://wiki.gridcoin.us/Wallet_Auto-unlock_for_staking