Version 1.57C

Apologies in advance if the answer was posted elsewhere. I'm unable to find it.

Gotta say, i dread the upgrades but so far, this one is way better than the old one! But having a few issues and i'll post them separately so others can benefit.

When on the admin home, if i click tools--who is online I get this message in a new blank page with these words on top:
WARNING: An Error occurred, please refresh the page and try again.If you were entering information, press the BACK button in your browser and re-check the information you had entered to be sure you left no blank fields.

Then, I the admin home page itself, under the new customers table i get this warning which is the same:
WARNING: An Error occurred, please refresh the page and try again.If you were entering information, press the BACK button in your browser and re-check the information you had entered to be sure you left no blank fields.

Few more minor things but will post it in another question. Thank you.