Written by Topher Kessler
Many times when you log into a network resource or access a system setting you will be prompted for a password, with the option to save the password in your keychain. This convenience allows you to access common items without needing to enter passwords every time you with to access those items; however, sometimes certain problems may prevent the system from properly retrieving the password.
Apple discussion poster "Damon S." writes:
"I have been having an issue with my MacBook refusing to remember the password for my Time Capsule. I have an external hard drive attached to my Time Capsule which stores all of my school files....When logging in to the Time Capsule, I have always selected the checkbox to save the Time Capsule password in my keychain. Yet, whenever I go to use it later, OS X doesn't remember my password and I have to enter it in again."
There are several approaches to tackling this and similar problems, which include running maintenance routines and removing keychain entries and preference files.
Since problems with passwords are likely due to the keychain, open the "Keychain Access" utility and run the "Keychain First Aid" routine (available in the "Keychain Access" menu) on all keychains. After this, if the problem still persists, try running a permissions fix on the boot drive using "Disk Utility", which should ensure all files on the boot drive are properly accessible.
A word of caution: you should consider running a permissions verification on the boot drive first, and then ensure there are no strange permissions in the verification output such as setting the permissions flags on files to being empty (ie, "?---------", which was seen after people applied the recent 10.5.8 system update). After verification checks out, run the permissions fix.
Remove keychain and preference files
Sometimes a fault in a keychain entry that gets overlooked by the keychain first aid routine may prevent it from being accessed by the relevant applications to which it is assigned. Removing the entry from the keychain will have the application refresh it with a new and properly accessible one. This will only require you to launch the application again and supply your password when prompted, checking the box to store it in your keychain.
In addition to keychain entries, a faulty preference file can prevent an application from accessing resources such as keychains. Locating and removing the relevant preference files for the application in the /username/Library/Preferences/ folder may allow the application to access the keychain again.
Topher has been an avid Mac user for the past 10-15 years, and has been a contributing author to MacFixIt for just over a year now. One of his diehard passions has been troubleshooting Mac problems and making the best use of Macs and Apple hardware both for family and friends, as well as in the workplace. He and the newly formed MacFixIt team are hoping to bring enhanced and more personable content to our readers, and keep the MacFixIt community going here at CNET. If you have questions or comments for Topher or the other MacFixIt editors, feel free to contact us at http://www.macfixit.com/contactResources