How can I change the date format?
I prefer to have the date displayed either
dd/mm/yy or yy/mm/dd
I prefer to have the date displayed either
dd/mm/yy
or yy/mm/dd
ప్రత్యుత్తరాలన్నీ (1)
Thunderbird should "borrow" the date format used elsewhere in your OS. Do you have either of those formats set up as your global preference in your computer's settings?
Given the two formats you have described, I take it you are getting the third option, mm/dd/yy, i.e. US style. Is your computer set to an appropriate locale and keyboard layout?