Recently, I was trying to register a Sonicwall TZ100 unit, however it will fail with an error message:

“Connection Failure – SSL negotiation with the license manager server has failed. This could be caused by an incorrect date/time setting on your firewall”

The date and time was fine. It turns out to be the issue was related to the changes with SSL key strength on the licensing servers. This article explains what to do:

I simply downloaded my keyset from, applied it, then was able to install the new firmware and problem solved.