WPyogi on "Error 500 after activating jetpack"

You will need to use FTP to access your site - here's the info on FTP on BH:

https://my.bluehost.com/cgi/help/ftpaccounts

Once you get that set up, first deactivate your plugins by changing the name on the plugins folder:

wordpress
   wp-content
       pluginsHOLD (change the name here)

IF that does not fix it, what theme are you using?