Re: Blogs Directory throwing and “operand types” fatal error
You shouldn’t be getting an error if you are using a recent version of bp. Not sure exactly when this got introduced but the current version give out an error message like this ‘[Adjust Time Zone]’ in place of the invalid recent activity date.
From this thread: https://buddypress.org/forums/topic.php?id=2437#post-13341
The problem is you need to adjust your time zone. 
For the "time since" to work correctly, the timezone setting
for your root blog has to match the time on your server.
You can change it under "Settings > General" in your /wp-admin/ area.(Andy Peatling)
