My Birthday calendar settings recently changed from 1 week's notice to a default (?) of 15 mins. (not by me).  I've had to go through laboriously changing them back - there's a risk of some very disappointed children out there! This is the second time it has happened in the last year.

Firstly, what causes the change? Could it be the clean-up program CCleaner that I run now and again?

Secondly, is there a way I can restore all the Birthday settings to 1 week without doing each one separately?

Regards, Brianfromenfield