Older generations of AM-4 with (firmware 3 or below) have the following Default Settings:
Current version of AM-4 (Firmware 4.63) have the following Default Settings:
If everything else fails, let's try setting up a new password via AMI-Terminal.
Under Custom String
Set FTP User Name: "nUS"h0D (where n=user name up to 32 Characters) "adminUS"h0D and click on Send
You should see R<0D> as response
Now let's setup the password...
Set FTP password: "pPW"h0D (where p=password up to 32 Characters) "passwordPW"h0D
Your new FTP User and Password info should be as follow: