Latest version blocks login

The latest version (4.1.1) of JetPack is blocking users from logging into my blog. I deactivated other plugins thinking there might be a conflict. That did not cure the problem. So I deactivated JetPack and the login problem was solved. The prior version of JetPack did not cause this problem.

I uninstalled and reinstalled, with the same blocking results. Any suggestions and is anyone else having similar problems.

https://wordpress.org/plugins/comments/