Unable to access Web GUI

[yealinky]

I have only tried to reboot but it did not work. Holding off on reset.

I have the same problem with a T41. Upgraded to T41-36.82.0.20.rom from T41-36.81.0.110.rom and cannot access via GUI. Sometimes it will not connect. Sometimes it gives "Secure Connection Failed" error:
"An error occurred during a connection to xxx.xxx.xxx.xxx. You have received an invalid certificate. Please contact the server administrator or email correspondent and give them the following information: Your certificate contains the same serial number as another certificate issued by the certificate authority. Please get a new certificate containing a unique serial number. Error code: SEC_ERROR_REUSED_ISSUER_AND_SERIAL
The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
Please contact the website owners to inform them of this problem."

I have only tried to reboot but it did not work. Holding off on reset.