Australis13

He’s safe if he works in MATLAB or other languages that use one-based indexing. He’s a dead man if she works out most lists are zero-based.

True. I guess given that the way I’ve always done it here (one contacts the bank directly to open a new joint account) rather than trying to add a second person to an existing account, I hadn’t considered that approach. Still, I can somewhat understand the rationale behind this design.

Unfortunately this somewhat makes sense… Now, if her account has been closed, then this is a design flaw. But if it’s still there - just hasn’t been used in ages - then this sanity-check makes sense to prevent fraud.