R500 firmware upgrade faild

[sunzi888]

I have 3 very old R500 APs in my home that were installed by previous home owner and were controlled by a zone director 1200.  But I was not able to access the controller.  I had to build a new home network on my own.  Now I want to take over all 3 R500.  I did reset on this first r500 AP, and logged into the onboard web interface at 192.168.0.1.  I was able to use the local upgrade FW option to point to the new FW image on my laptop, but it seems that the upgrade did not going through correctly because the duration is too short, maybe 10-15 seconds.  It flicked back to the login page.  After that I could not bring up the login page via the IP: 192.168.0.1, and display following error message:

"This site can't provide a secure connection

192.168.0.1 uses an unsupported protocol.

ERR_SSL_VERSION_OR_CIPHER_MISMATCH"

I repeatedly try to reset the AP but has no result.  Only power lit solid green, all other lights dim.

I suspected that the firmware is corrupted due to the unsuccessful firmware upgrade process.  But how can I take from here to fix it?  Is there any other method that I could use to upgrade the firmware or even better to upgrade to unleashed firmware?  Thanks very much for all the help I can get!!!