[I can't Login]

Sorry, what does it mean?

[I can't Login]

Did not work. I quit! 

[I can't Login]

I can not solve it, but I think there is something blocking the connection because the same message appears when I open Adobe Creative Cloud, but I do not know how to solve. 

[I can't Login]

Quote

 

"Login failed.
Often this means that your computer's clock is set incorrectly.
Please go to the ControlPanels and make sure the time and date
are set correctly.
Also check that your network and firewall are set up correctly.
If you continue to receive this error, please go
to the Support section of the Secondlife.com web site
and report the problem."

 

I already tried everything, the date and the clock are correct.
It's been 3 days that I can not log into this computer in any of my avatars.
I can usually get into another computer on any avatar.
I have already tried the Second Life viewer and Firestorm, the error remains.
I have no idea how to solve this. Thanks.