Answers...

to commonly asked questions.

Don't encrypt time machine drives

My external backup drive is asking for a password and I don't know what it wants.
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Looks like you may have chosen to “encrypt” the backup hard drive that Time Machine uses and may not know the password. I don’t personally recommend people use encrypted backups for this exact reason. Easiest thing to do here would be to just wipe the external drive and let Time Machine just start over again.
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