In 2008 there was an electronic bank run.

From what I understand bank runs occur due to the fractional reserve banking system. The actual real money you can hold on your hand are a fraction of the total money in banks. So if everyone goes to the ATM and gets the money in their hand, it means that the bank runs out of the "real money" and people can't withdraw this "real money".

So if the same number of people, instead of withdrawing from the ATMs, do electronic transactions that eg get their money from a bank to another bank (or any other institution) how can there be a bank run?