Keychain Access: cannot add a new item: user name or passphrase not correct

When trying to add a new item to "Keychain Access", the application suddenly refused to do so. Error message:
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Title: An error has occurred. Unable to add an item to the current keychain.
Message: The user name or passphrase you entered is not correct.
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I never need a user name neither passphrase to store a new entry in the keychain.

Steps to resolve:
1. Restarting app: no good
2. Repair disk permissions: no improvement
3. Verify disk: no errors found
4. Verfify Keychain First Aid menu from with Keychain.app
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Verification started
Checking keychain configuration for User Name (user ID=501)
Home directory is /Users/shortname
Checked login keychain
Checked password for ~/Library/Keychains/login.keychain
Checked settings for ~/Library/Keychains/login.keychain
Settings for ~/Library/Keychains/login.keychain may cause the keychain to be locked
Current values: lockOnSleep=no, autoLock=never
Checked default keychain
Checked keychain search list
Checked contents of ~/Library/Keychains/login.keychain
Checked contents of ~/Library/Keychains/Microsoft IntermediateCertificates
Verification completed
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and a repair:
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Repair started
Checking keychain configuration for User Name (user ID=501)
Home directory is /Users/shortname
Checked login keychain
Checked password for ~/Library/Keychains/login.keychain
Checked settings for ~/Library/Keychains/login.keychain
Settings for ~/Library/Keychains/login.keychain may cause the keychain to be locked
Current values: lockOnSleep=no, autoLock=never
Settings corrected on ~/Library/Keychains/login.keychain
Checked default keychain
Checked keychain search list
Checked contents of ~/Library/Keychains/login.keychain
Checked contents of ~/Library/Keychains/Microsoft IntermediateCertificates
Problems successfully repaired
Repair completed
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The First Aid Menu, option repair, solved this problem.

Hopefully by documenting this, this helps another one who experiences the same error, in resolving.