First let me clarify what is the password that you are referring to. If it's the password for the wireless network, there is no need to reset the router. All you need to do is access the router setup page and verify the correct password or network key. You can use the hub I created as a guide to do this. Click on the link below.
Now if it's the "router" password (by default is admin) is the issue, if you can't recall and tried all possible passwords; resetting the router to the factory defaults will be the last resort. I hope I was able to help you with your problem.
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