▪ If you've set your keychain to lock after a period of time, or when your computer goes to sleep, your keychain is locked, and you'll see a message asking for your keychain password. To change your keychain settings, open Keychain Access, located in Applications/Utilities (or click the link below). Select a keychain and choose Edit > Change Settings for Keychain <keychain name>. Deselect "Lock after <number of minutes> of inactivity" and "Lock when sleeping."
▪ Open Keychain Access, located in Applications/Utilities (or click the link below). Choose Window > Keychain First Aid. Select a mail account and click Verify, then click the Start button. A log appears listing errors. Click Repair, then click the Start button