I have an APC Rack PDU AP7920 (hardware revision B2, manufactured 07/21/2012). When I log in via telnet I get:

American Power Conversion               Network Management Card AOS      v3.3.4                                          
(c) Copyright 2005 All Rights Reserved  Rack PDU APP                     v3.3.3     

I would like to upgrade the firmware. On the APC website, I found two options (they are very hidden for some reason): apc_hw02_aos390_rpdu374.exe and apc_hw02_aos392_rpdu392.exe (i.e., v3.9.0/3.7.4 and 3.9.2/3.9.2).

After executing go.bat and entering correct IP address, username and password, I get for both:

Checking network connection ...  ERROR!!! Login unsuccessful.

That's definitely not true: IP and login details are 100% correct. How can I upgrade this?

1 Answer 1


Probably you didn't read the log file. You need to enable the FTP server. The error message could have been more explicit in the dos shell, I agree.

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