Hi, this may help: Procedure to download the update catalog
I was running an older 3.2 version when I first ran into this problem. Updated to 3.4.0 via the built-in updater. Same problem. The system can see the R6525 machine and can run a firmware compliance report, but I can't do a firmware upgrade from within OME. The R6525 is listed on the support matrix, so I'm not sure what the problem is. It came with Lifecycle v4.10.10.10.
R6525 not supporting firmware update