I'm running a iMac with 10.9.5. Recently I installed Adobe CC, and ever since, I've been having issues with my admin password. My computer no longer recognizes it. So I'm effectively unable to update or install programs, or change any settings. Somehow it shifted from requiring a login password at start up, to logging in automatically, and then I get the message "accountsd wants to use the login keychain." The admin password works in this case. I reset my keychain, but that didn't solve the problem. I tried to repair the keychain, but that requires an admin password and in this case it doesn't work. I'm at a loss. Any ideas?
I'd reset the password from the Recovery HD and then change it in the Keychain afterwards.
Have a look at Reset Forgotten Admin Password OSX 10.10 Yosemite, which is also applicable for 10.8 and later.
Reboot (Apple menu > Restart) to the Recovery HD holding down Command-R during startup.
Go to the Utilities menu and select: Terminal
In the Terminal type resetpassword and press Enter.
In the Reset Password screen follow the directions.
Go to the Apple menu and click: Restart
Then reset the password in the Keychain after booting back normally to the Desktop.