Thank you BDAqua.
I rest the keychain password to match my user/admin password. However, it seems there are 3 keychains in Keychains Access - 'login keychain', 'System keychain' and 'X509 keychain'. The resetting only seems to have affected the 'login keychain'. Why is that?
When I'm asked for the keychain password in 'login keychain' it accepts the new password. But when I'm asked for the keychain password in 'System keychain' it rejects it 3 times and asks me to try later. I've changed the permission of the file 'System.keychain' (in Library > Keychains) from 'system' to 'me/owner' (via Command-I) but this has made no difference. Do I have reset the password for the 'System keychain' too? Is this possibe?
The newly created ('renamed') 'login keychain' was empty. The old one, which I'd dragged to the desktop, contained all the passwords I didn't want to lose. I put it back (into user > library > Keychains) and trashed the new empty 'login keychain'. I then ran Keychain First Aid 'Verify' which detected the new keychain was missing. I then ran Keychain First Aid 'Repair' which fixed it. I now had access to the old 'login keychain' with the new password. Does this make sense to you?
Could you please deal with my 3 questions?
Thanks, iHope