Fatal error: Call to undefined function mb_strlen()

Question

I\'m trying to make a donation center which I use the source code from Totorialzine.

Everything works fine for me at this moment so far but the only problem I was st

Answer 1

This worked for me on Debian stretch

sudo apt-get update
sudo apt install php-mbstring
service apache2 restart

Answer 2

For me the following command did the trick

sudo apt install php-mbstring