Can't login to JGS524ev2 after v2.6.0.43 firmware upgrade from Prosafe Client

I upgraded my Prosafe Plus Utility to 2.7.7 and then attempted to upgrade the firmware on my JGS524ev2 to v2.6.0.43 (both versions are identified as the latest version for this device on the Netgear support page).

After upgrading the firmware, I am unable to login to the switch from the client.  I am able to login to the switch using it's IP via a browser.  And by doing so, I can confirm the switch is running the v2.6.043 firmware.  Upon entering my password, I get an error windows entitlted 'Login'.  The text in the pop is "Command is not supported by agent!".  I was able to use the Prosafe Plus Utility 2.7.7 to login into the switch before the upgrade.

I had this problem one before back in 2017.  The solution was to upgrade the Prosafe Plus Utility client software.  However, I've done that and am experiencing this problem again.  I uninstalled the Prosafe client and it's other software (winpcap and Adobe Air) and reinstalled it (same result).

Thanks in advance for your recommendations.